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Listing of NCL Functions by Category
Alphabetical listing  Function type listing  Browsable listing



Array creators
fspan  Creates an array of evenlyspaced floating point numbers. 
generate_unique_indices  Generate unique random indices (subscripts). 
ispan  Creates an array of equallyspaced integer, long, or int64 values. 
nice_mnmxintvl  Calculates "nice" values for endpoints and spacing to be used for creating a series of equallyspaced levels through the data domain. 
Array manipulators
array_append_record  Attaches [appends] additional records [leftmost dimension] to a previously existing array. 
conform  Expands an array or scalar so that it conforms to the shape of the given variable. 
conform_dims  Expands an array or scalar so that it conforms to the shape of the given dimension sizes. 
crossp3  Compute cross product of multiple vectors of length 3. 
dim_gbits  Unpacks bit chunks from the rightmost dimension of the input array. 
epsZero  Sets all values in input array to zero that are +/ a user supplied epsilon about zero. 
get1Dindex_Collapse  Returns a one dimensional array of subscript indices that DO NOT match the values contained in a user specified list. 
get1Dindex_Exclude  Returns a one dimensional array of subscript indices that DO NOT match the values contained in a user specified list. 
getbitsone  Unpacks onebit chunks from the input array. 
grid2triple  Converts a twodimensional grid with onedimensional coordinate variables to an array where each grid value is associated with its coordinates. 
ind_resolve  Resolves a single list of indices to their multidimensional representation. 
mask  Masks a multidimensional array against another given a single mask value. 
merge_levels_sfc  Merges a multiple level variable with the corresponding surface variable. 
ndtooned  Converts a multidimensional array to a onedimensional array. 
onedtond  Converts a onedimensional array to a multidimensional array. 
reshape  Reshapes a multidimensional array to another multidimensional array. 
reshape_ind  Places values from a smaller onedimensional array to a larger onedimensional array, and reshapes it. 
rm_single_dims  Removes (squeezes) singleton (degenerate) dimensions from an array while preserving meta data. 
sparse_matrix_mult  Multiples a sparse matrix with a dense matrix. Function under construction. Calling arguments may change. 
transpose  Transposes a matrix and copies all attributes and coordinate variables. 
where  Performs array assignments based on a conditional array. 
Array query
all  Returns True if all the elements of the input evaluate as True. 
any  Returns True if any of the values of its input evaluate as True. 
closest_val  Finds the index value in a monotonically increasing one dimensional array closest to a desired value. 
dimsizes  Returns the dimension sizes of the input variable. 
get1Dindex  Finds the indices of a onedimensional array which exactly match a user specified list of values. 
getind_latlon2d  Finds the indices (subscripts) of twodimensional latitude/longitude arrays closest to a user specified latitude/longitude coordinate pair. 
ind  Returns the indices where the input is True. 
ind_nearest_coord  Determine indices of locations closest to a coordinate array. 
isMonotonic  Check a one dimensional array to see if it is monotonic. 
local_max_1d  Determines the relative maxima for a 1dimensional array. 
local_min_1d  Determines the relative minima for a 1dimensional array. 
maxind  Returns the index of the first occurrence of a maximum value. 
minind  Returns the index of the first occurrence of a minimum value. 
month_to_annual  Converts monthly values to annual values. 
month_to_annual_weighted  Converts monthly values to annual values weighted by the number of days in a month. 
monthly_total_to_daily_mean  Convert monthly total values [eg, precipitation] to "per day" values. 
niceLatLon2D  Check two dimensional map coordinates to see if they have a "nice" structure. 
num  Counts the number of True values in the input. 
region_ind  Returns the indices (subscripts) of twodimensional latitude/longitude arrays that span user specified latitude/longitude boundaries. 
CESM
angmom_atm  Calculates the atmosphere's relative angular momentum. 
band_pass_area_time  Create a time series of area averages; band pass filter the resulting area averaged time series and calculate other statistics. 
band_pass_area_time_plot  Generate a plot using the output from band_pass_area_time. 
band_pass_hovmueller  Create a bandpass filtered time series suitable for a time vs longitude (Hovmueller) plot. 
band_pass_hovmueller_plot  Generate a plot using the output from band_pass_hovmueller. 
band_pass_latlon_time  Create bandpass filtered series at each lat/lon grid point. 
band_pass_latlon_time_plot  Generate a plot using the output from band_pass_latlon_time. 
cz2ccm  Computes geopotential height in hybrid coordinates. 
decomposeSymAsym  Decompose a variable which is symmetric about the equator into symmetric and asymmetric parts. 
depth_to_pres  Convert ocean depth to pressure. 
dpres_hybrid_ccm  Calculates the pressure differences of a hybrid coordinate system. 
dpres_plevel  Calculates the pressure layer thicknesses of a constant pressure level coordinate system. 
dpres_plevel_Wrap  Calculates the pressure layer thicknesses of a constant pressure level coordinate system. 
dz_height  Calculates the height layer thicknesses at each grid point over varying surface terrain. 
kf_filter  Extract equatorial waves by filtering in the WheelerKiladis wavenumberfrequency domain. 
mixed_layer_depth  Calculates a quantity derived from the Potential Density of significance. (Documentation under construction.) 
mjo_cross  Calculate spacetime cross spectrum over multiple segments. 
mjo_cross_coh2pha  Calculate spacetime coherencesquared and phase using the array returned by mjo_cross_segment . 
mjo_cross_plot  Plot coherencesquared and phase spectra as returned by mjo_cross. 
mjo_cross_segment  Calculate spacetime cross spectrum for a single time segment. 
mjo_phase_background  Plot background for MJO phasespace diagram. 
mjo_space_time_cross  Calculate spacetime cross spectrum over multiple segments. 
mjo_spectra  Driver to calculate and plot seasonal spectra via segment averaging as defined by the USCLIVAR MJO diagnostics website . 
mjo_spectra_season  Calculates seasonal spectra via segment averaging as defined by the USCLIVAR MJO diagnostics website . 
mjo_wavenum_freq_season  Calculates wavenumberfrequency spectar via seasonal averaging as defined by the USCLIVAR MJO diagnostics website . 
mjo_wavenum_freq_season_plot  Plot wavenumberfrequency spectra as returned by mjo_wavenum_freq_season. 
mjo_xcor_lag_ovly  Plot lagged crosscorrelations as returned by mjo_xcor_lag_season. 
mjo_xcor_lag_ovly_panel  Plot lagged crosscorrelations as returned by mjo_xcor_lag_season as panels. 
mjo_xcor_lag_season  Calculates lagged correlations between a reference series and gridded data as specified by the USCLIVAR MJO diagnostics website . 
moc_globe_atl  Facilitates calculating the meridional overturning circulation for the globe and Atlantic. 
omega_ccm  Calculates omega [vertical pressure velocity] using the model diagnostic method. 
omega_ccm_driver  Computes vertical pressure velocity [omega] via model diagnostic code. 
pop_remap  Regrids a POP ocean model grid to another grid. 
PopLatLon  Regrids a scalar variable on a POP grid to a lat/lon grid or viceversa. 
PopLatLonV  Converts vectors on a POP grid to a lat/lon grid and viceversa. 
potmp_insitu_ocn  Calculate seawater potential temperature at an arbitrary reference pressure given insitu temperature, salinity and depth. 
pres_hybrid_ccm  Calculates pressure at the hybrid levels. 
resolveWavesHayashi  Reorder the complex coefficients returned by cfftf to resolve the progressive and retrogressive waves. 
vinth2p  Interpolates CAM (Community Atmosphere Model) hybrid coordinates to pressure coordinates. 
vinth2p_ecmwf  Interpolates CESM hybrid coordinates to pressure coordinates but uses an ECMWF formulation to extrapolate values below ground. 
vinth2p_ecmwf_nodes  Interpolates CESM hybrid coordinates to pressure coordinates but uses an ECMWF formulation to extrapolate values below ground. 
vinth2p_nodes  Interpolates CESM hybrid coordinates to pressure coordinates on an unstructured grid. 
vintp2p_ecmwf  Interpolates data at multidimensional pressure levels to constant pressure coordinates and uses an ECMWF formulation to extrapolate values below ground. 
wgt_vert_avg_beta  Computes weighted vertical average or sum using pressure thickness and beta factors. 
wgt_volave_ccm  Calculates the volume average of a quantity from the CCM using weights. 
wgt_volrmse_ccm  Calculates a weighted volume rootmeansquaredifference between two variables from the CCM. 
wkSpaceTime  Calculates WheelerKiladis spacetime spectra. 
wkSpaceTime_cam  Calculates WheelerKiladis spacetime spectra using a generic CAM interface. 
Climatology
calcDayAnomTLL  Calculates daily anomalies from a daily data climatology. 
calcMonAnomLLLT  Calculates monthly anomalies by subtracting the long term mean from each point (lev,lat,lon,time version) 
calcMonAnomLLT  Calculates monthly anomalies by subtracting the long term mean from each point (lat,lon,time version) 
calcMonAnomTLL  Calculates monthly anomalies by subtracting the long term mean from each point (time,lat,lon version) 
calcMonAnomTLLL  Calculates monthly anomalies by subtracting the long term mean from each point: (time,lev,lat,lon) version. 
clmDayTLL  Calculates long term daily means (daily climatology) from daily data. 
clmDayTLLL  Calculates long term daily means (daily climatology) from daily data. 
clmMon2clmDay  Create a daily climatology from a monthly climatology. 
clmMonLLLT  Calculates long term monthly means (monthly climatology) from monthly data: (lev,lat,lon,time) version. 
clmMonLLT  Calculates long term monthly means (monthly climatology) from monthly data (lat,lon,time version) 
clmMonTLL  Calculates long term monthly means (monthly climatology) from monthly data: (time,lat,lon) version 
clmMonTLLL  Calculates long term monthly means (monthly climatology) from monthly data: (time,lev,lat,lon) version 
month_to_season  Computes a userspecified threemonth seasonal mean (DJF, JFM, FMA, MAM, AMJ, MJJ, JJA, JAS, ASO, SON, OND, NDJ). 
month_to_season12  Computes threemonth seasonal means (DJF, JFM, FMA, MAM, AMJ, MJJ, JJA, JAS, ASO, SON, OND, NDJ). 
month_to_seasonN  Computes a userspecified list of threemonth seasonal means (DJF, JFM, FMA, MAM, AMJ, MJJ, JJA, JAS, ASO, SON, OND, NDJ). 
rmAnnCycle1D  Removes annual cycle from a onedimensional time series. 
rmMonAnnCycLLLT  Removes the annual cycle from "monthly" data. 
rmMonAnnCycLLT  Removes the annual cycle from "monthly" data. 
rmMonAnnCycTLL  Removes the annual cycle from "monthly" data. 
smthClmDayTLL  Calculates a smooth mean daily annual cycle for an array nominally dimensioned (Time,Lat,Lon). 
smthClmDayTLLL  Calculates a smooth mean daily annual cycle for an array nominally dimensioned (Time,Level,Lat,Lon). 
stdMonLLLT  Calculates standard deviations of monthly means. 
stdMonLLT  Calculates standard deviations of monthly means. 
stdMonTLL  Calculates standard deviations of monthly means. 
stdMonTLLL  Calculates standard deviations of monthly means. 
Color routines
color_index_to_rgba  Converts an absolute color index to its equivalent RGBA quadruplet 
ColorNegDashZeroPosContour  Sets the negative contours to dashed, and colors the negative, positive, and zero contours to userspecified colors. 
ColorShadeLeGeContour 
Shades contour regions given low and high values and two colors. (Superceded by gsn_contour_shade as of version 4.3.0.) 
get_color_index  Chooses a color index for a scalar value, given a color map and a range of values. 
get_color_rgba  Chooses an RGB triplet or RGBA quadruplet for a scalar value, given a color map and a range of values. 
GetFillColor  Chooses a color from a group of RGB triplets based upon a secondary scalar field (deprecated version). 
GetFillColorIndex  Chooses from a list of color table indices based upon a secondary scalar field (deprecated version). 
gsn_contour_shade  Shades contour regions given low and/or high values using colors or patterns. 
gsn_define_colormap  Defines a color map for the given workstation. 
gsn_draw_colormap  Draws the current color map for the given workstation. 
gsn_draw_named_colors  Draws the given list of named colors. 
gsn_merge_colormaps  Merges two color maps and sets this as the color map for the given workstation. 
gsn_retrieve_colormap  Retrieves a color map for the given workstation. 
gsn_reverse_colormap  Reverses the color map for the given workstation. 
hlsrgb  Converts HLS color values to RGB. 
hsv2rgb  Maps values from the HSV color model to the RGB color model (deprecated). 
hsvrgb  Converts HSV color values to RGB. 
namedcolor2rgb  Returns the RGB triplets of the given list of named colors. 
namedcolor2rgba  Returns the RGBA quadruplets of the given list of named colors. 
NhlFreeColor  Removes one or more color entries from one or more workstations. 
NhlGetNamedColorIndex  Returns color map indexes that match the given color names in the color maps of the given workstations. 
NhlIsAllocatedColor  Queries a list of workstations to determine whether or not the given color indexes have been allocated. 
NhlNewColor  Allocates new workstation color indexes. 
NhlPalGetDefined  Returns a list of available color maps. 
NhlSetColor  Sets the colors for a given list of color indexes and workstations. 
read_colormap_file  Reads an NCL system colormap file or a userdefined colormap. 
rgba_to_color_index  Converts RGBA quadruplets to their encoded integer equivalent absolute color indexes 
rgbhls  Converts RGB color values to HLS. 
rgbhsv  Converts RGB color values to HSV. 
RGBtoCmap  Reads a text file of RGB triplets and converts them to a colormap. 
rgbyiq  Converts RGB color values to YIQ values. 
setColorContourClear  Sets the color contours between two given levels transparent. 
span_color_indexes  Given the number of desired color values, return an array of indexes that nicely span the given color map. 
span_color_rgba  Given the number of desired color values, return an array of RGB triplets or RGBA quadruplets that nicely span the given color map. 
span_named_colors  Returns an RGB array that is a span between given list of named colors. 
yiqrgb  Converts YIQ color values to RGB. 
Cumulative distribution functions
cdfbin_p  Calculates the binomial density of a cumulative distribution function. 
cdfbin_pr  Calculates the probability of success of each trial of a cumulative distribution function. 
cdfbin_s  Calculates the number of successes of a cumulative distribution function. 
cdfbin_xn  Calculates the number of binomial trials of a cumulative distribution function. 
cdfchi_p  Calculates the intergral of a cumulative chisquare distribution function. 
cdfchi_x  Calculates the upper limit of intergration of a cumulative chisquare distribution function. 
cdfgam_p  Calculates the integral of a cumulative gamma distribution function. 
cdfgam_x  Calculates the upper limit of intergration of a cumulative gamma distribution function. 
cdfnor_p  Calculates the integral of a cumulative normal distribution function. 
cdfnor_x  Calculates the upper limit of integration of a cumulative normal distribution function. 
Date routines
calendar_decode2  Translates numeric time coordinates to calendar times. 
cd_calendar  Converts a mixed Julian/Gregorian date to a UTreferenced date. 
cd_convert  Converts a time variable from one set of units to another. 
cd_inv_calendar  Converts a UTreferenced date to a mixed Julian/Gregorian date. 
cd_string  Converts time values into nicely formatted strings. 
day_of_week  Calculates the day of the week given month, day, and year (Gregorian calendar). 
day_of_year  Calculates the day of the year given month, day, and year. 
days_in_month  Calculates the number of days in a month given month, day, and year. 
greg2jul  Converts a Gregorian date to a Julian day. 
grib_stime2itime  Converts grib initial_time (string) to time (integer). 
isleapyear  Determines if a given year is a leap year. 
jul2greg  Converts a Julian day to a Gregorian date. 
monthday  Calculates a concatenated month_day given a day and year. 
time_axis_labels  Sets resources necessary to draw nice tickmark labels using a format of date/time on an axis. 
ut_calendar  Converts a mixed Julian/Gregorian date to a UTreferenced date (deprecated; use cd_calendar). 
ut_convert  Converts a time variable from one set of units to another (deprecated; use cd_convert). 
ut_inv_calendar  Converts a UTreferenced date to a mixed Julian/Gregorian date (deprecated; use cd_inv_calendar). 
ut_string  Converts time values into nicely formatted strings (deprecated; use cd_string) 
yyyyddd_to_yyyymmdd  Given concatenated year and dayofyear (yyyyddd) create a onedimensional array containing concatenated year, month and dayofmonth [yyyymmdd] values. 
yyyymm_time  Creates a onedimensional array containing yearmonth [yyyymm] values. 
yyyymm_to_yyyyfrac  Converts a one dimensional array containing yyyymm values to yyyy and fractional year. 
yyyymmdd_time  Creates a onedimensional array containing yearmonthday [yyyymmdd] values. 
yyyymmdd_to_yyyyddd  Given concatenated yearmonthday_of_month (yyyymmdd) create a onedimensional array containing concatenated year and day_of_year [yyyyddd] values. 
yyyymmdd_to_yyyyfrac  Converts a one dimensional array containing yyyymmdd values to yyyy and fractional year. 
yyyymmddhh_time  Creates a onedimensional array containing yearmonthday [yyyymmddhh] values. 
yyyymmddhh_to_yyyyfrac  Converts a one dimensional array containing yyyymmddhh values to yyyy and fractional year. 
Empirical orthogonal functions
eof2data  Reconstructs a data set from EOFs and EOF time series. 
eof_varimax  Rotates EOFs using the using Kaiser row normalization and the varimax criterion (deprecated version). 
eofcor  Calculates empirical orthogonal functions via a correlation matrix (NCL's original function). 
eofcor_pcmsg  Calculates empirical orthogonal functions via a correlation matrix (missing values allowed) (deprecated version). 
eofcor_ts  Calculates the time series of the amplitudes associated with each eigenvalue in an EOF which was calculated using a correlation matrix. 
eofcor_Wrap  Calculates empirical orthogonal functions and retains meta data. (NCL's original function). 
eofcov  Calculates empirical orthogonal functions via a covariance matrix (original version). 
eofcov_pcmsg  Calculates empirical orthogonal functions via a covariance matrix (missing values allowed)(deprecated version). 
eofcov_ts  Calculates the time series of the amplitudes associated with each eigenvalue in an EOF which was calculated using a covariance matrix. 
eofcov_Wrap  Calculates empirical orthogonal functions and retains meta data. (NCL's original EOF function). 
eofunc  Compute empirical orthogonal functions (EOFs, aka: Principal Component Analysis). 
eofunc_ts  Calculates the time series of the amplitudes associated with each eigenvalue in an EOF. 
eofunc_ts_Wrap  Calculates the time series of the amplitudes associated with each eigenvalue in an EOF and retains metadata. 
eofunc_varimax  Rotates EOFs using the using Kaiser row normalization and the varimax criterion. 
eofunc_varimax_reorder  Reorder the results returned by eof_varimax into descending order by percent variance explained. 
eofunc_varimax_Wrap  Rotates EOFs using the using Kaiser row normalization and the varimax criterion and retains metadata. 
eofunc_Wrap  Computes empirical orthogonal functions (aka: Principal Component Analysis, Eigen Analysis) and retains metadata. 
ESMF
curvilinear_to_SCRIP  Writes the description of a curvilinear grid to a SCRIP file. 
ESMF_regrid  Regrids data from one lat/lon grid to another, using ESMF software. 
ESMF_regrid_gen_weights  Writes a weight file using the offline ESMF weight generator. 
ESMF_regrid_with_weights  Using the provided weight file, regrids data from one lat/lon grid to another. 
latlon_to_SCRIP  Writes the description of a lat/lon grid to a SCRIP file. 
rectilinear_to_SCRIP  Writes the description of a rectilinear grid to a SCRIP file. 
unstructured_to_ESMF  Writes the description of an unstructured grid to an ESMF file. 
File IO
addfile  Opens a data file that is (or is to be) written in a supported file format. 
addfiles  Creates a reference that spans multiple data files. 
addfiles_GetVar  Creates a reference that spans multiple data files and returns metadata. (deprecated: see addfiles) 
asciiread  Reads a file that contains ASCII representations of basic data types. 
asciiwrite  Creates an ascii text file of numeric or string data type. 
cbinread  Reads binary files created using the C block I/O function write. 
cbinwrite  Creates a binary file in raw C block I/O format for a numeric data type. 
craybinnumrec  Returns the number of unformatted sequential access Fortran records in a Cray COS blocked binary file. 
craybinrecread  Reads COS blocked unformatted sequential access Fortran binary files. 
fbindirread  Reads binary records written by a Fortran direct access write or C write. 
fbindirSwap  Reads bytereversed data and writes output file that can be read by fbindirread or cbinread (deprecated). 
fbindirwrite  Writes binary records to a file in manner analogous to fortran's "access=direct". 
fbinnumrec  Returns the number of unformatted sequential Fortran records in a binary file. 
fbinread  Reads one binary record that has been written using an UNFORMATTED FORTRAN write. 
fbinrecread  Reads unformatted sequential access Fortran binary files. 
fbinrecwrite  Writes a single unformatted sequential access Fortran record to a file. 
fbinseqSwap1  Byte swaps Fortran sequential files (deprecated). 
fbinseqSwap2  Byte swaps Fortran sequential files (more memory friendly) (deprecated). 
fbinwrite  Writes a single binary record to a file in manner analogous to fortran's "form=unformatted, access=sequential". 
fileattdef  Defines global (file) attributes associated with a supported file. 
filechunkdimdef  Defines chunking dimension names, dimension sizes, unlimited dimensions on a supported file. 
filedimdef  Defines dimension names, dimension sizes, unlimited dimensions on a supported file. 
fileexists  Checks for existence of any UNIX file. 
filegrpdef  Defines a list of group (names), for a supported file, or group. 
filevarattdef  Copies attributes from an input variable to one or more variables on a supported file. 
filevarchunkdef  Defines a list of variable names, variable var_types, and variable dimension names for a supported file. 
filevarcompressleveldef  Defines a list of variable names, variable var_types, and variable dimension names for a supported file. 
filevardef  Defines a list of variable names, variable types, and variable dimension names for a supported file. 
filevardimsizes  Returns the dimension sizes of variable on a supported file. 
getfiledimsizes  Returns a list of dimension sizes of the given file variable. 
getfilegrpnames  Returns an array of file group names in the specified supported file. 
getfilevaratts  Returns all attribute names associated with a variable on a supported file. 
getfilevardims  Returns all dimension names associated with a variable on a supported file. 
getfilevardimsizes  Returns the dimension sizes of variable on a supported file. 
getfilevarnames  Returns an array of file variable names in the specified supported file. 
getfilevartypes  Returns the types of the named variables stored in the given supported file. 
isfile  Returns True if input is of type file. 
isfilepresent  Checks if a supported file exists. 
isfilevar  Checks if specified file variables are defined in a file. 
isfilevaratt  Checks if specified file variable attributes are defined for a file variable. 
isfilevarcoord  Checks if a coordinate variable is defined in a file. 
isfilevardim  Checks if file variable dimensions are defined for a file variable. 
list_files  Lists all of the variables that reference files. 
list_filevars  Lists all of the variables associated with a specific file. 
ListCount  Queries the number of element(s) in a list. 
ListGetType  Queries the manner in which a variable of type list was created. 
ListIndex  Queries the index of a variable in a list. 
ListPop  Pop (out) an element from list. 
ListPush  Push a variable into the list. 
ListSetType  Specifies the manner in which a variable of type list is to be implemented. 
NewList  Create a list (type variable). 
numAsciiCol  Returns the number of columns in an ASCII file. 
numAsciiRow  Returns the number of rows in an ASCII file. 
readAsciiHead  Reads an ASCII file and returns just the header. 
readAsciiTable  Reads an ASCII file given the number of lines at the beginning and end of the file to ignore. 
setfileoption  Sets a number of fileformatspecific options. 
v5d_close  Closes a Vis5D+ format file. 
v5d_create  Creates a Vis5D+ format file. 
v5d_setLowLev  Sets the lowest vertical offset, in grid level, for each 3dimensional gridded variable in a Vis5D+ format file. 
v5d_setUnits  Sets a name for physical units for a variable in a Vis5D+ format file. 
v5d_write  Writes compressed data to a Vis5D+ format file. 
v5d_write_var  Writes a single 3dimensional gridded variable to a Vis5D+ format file. 
wrf_user_getvar  Extracts data from ARW WRF model output, and does basic diagnostics calculations. 
wrf_user_list_times  Extracts the list of available times in the ARW WRF model output. 
write_matrix  Writes nicelyformatted integer, float, or double precision twodimensional (2D) arrays to standard out or to a file. 
write_table  Writes all elements from a list (to a file). 
General applied math
abs  Returns the absolute value of numeric data. 
acos  Computes the inverse cosine of numeric types. 
arrayshift  Rearrange an array in a manner similar to Matlab's fftshift. 
asin  Computes the inverse sine of numeric types. 
atan  Computes the inverse tangent of numeric types. 
atan2  Computes the inverse tangent of (y/x) for numeric types. 
avg  Computes the average of a variable regardless of dimensionality. 
betainc  Evaluates the incomplete beta function. 
calculate_monthly_values  Calculate monthly values [avg, sum, min, max] from high frequency temporal values. 
cancor  Performs canonical correlation analysis between two sets of variables. 
cdft_p  Calculates the onesided probability given a tvalue and the degrees of freedom. 
cdft_t  Calculates the tvalue given the onesided probability and the degrees of freedom. 
ceil  Computes the smallest integer value larger than the input. 
center_finite_diff  Performs a centered finite difference operation on the rightmost dimension. 
center_finite_diff_n  Performs a centered finite difference operation on the given dimension. 
cfftb  Performs a backward complex discrete fourier transform [Fourier Synthesis]. 
cfftf  Performs a forward complex discrete fourier transform of a real periodic sequence. 
cfftf_frq_reorder  Reorders the data returned by cfftf. 
chiinv  Evaluates the inverse chisquared distribution function. 
cos  Computes the cosine of numeric types. 
cosh  Computes the hyperbolic cosine of numeric types. 
covcorm  Calculates a covariance or correlation matrix. 
covcorm_xy  Calculates a covariance or correlation matrix given two separate arrays. 
cumsum  Calculates the cumulative sum. 
decimalPlaces  Truncates or rounds to the number of decimal places specified 
dim_acumrun_n  Calculates individual accumulated sums of sequences ('runs') of a specified length. 
dim_avg  Computes the average of a variable's rightmost dimension at all other dimensions. 
dim_avg_n  Computes the average of a variable's given dimension(s) at all other dimensions. 
dim_avg_n_Wrap  Computes the average of a variable's given dimensions at all other dimensions and retains metadata. 
dim_avg_wgt  Computes the weighted average of a variable's rightmost dimension at all other dimensions. 
dim_avg_wgt_n  Computes the weighted average of a variable's given dimension at all other dimensions. 
dim_avg_wgt_n_Wrap  Computes the weighted average of a variable's given dimension at all other dimensions and retains metadata. 
dim_avg_wgt_Wrap  Computes the weighted average of a variable's rightmost dimension at all other dimensions and retains metadata. 
dim_avg_Wrap  Computes the average of a variable's rightmost dimension at all other dimensions and retains metadata. 
dim_cumsum  Calculates the cumulative sum along the rightmost dimension. 
dim_cumsum_n  Calculates the cumulative sum along the given dimension(s). 
dim_cumsum_n_Wrap  Calculates the cumulative sum along the given dimension(s) and retains meta data. 
dim_cumsum_Wrap  Calculates the cumulative sum along the rightmost dimension and retains meta data. 
dim_gamfit_n  Fit data to the two parameter gamma distribution. 
dim_max  Finds the maximum of a variable's rightmost dimension at all other dimensions. 
dim_max_n  Finds the maximum of a variable's given dimensions at all other dimensions. 
dim_max_n_Wrap  Computes the maximum of a variable's given dimensions at all other dimensions and retains metadata. 
dim_median  Computes the median of a variable's rightmost dimension at all other dimensions. 
dim_median_n  Computes the median of a variable's given dimensions at all other dimensions. 
dim_min  Finds the minimum of a variable's rightmost dimension at all other dimensions. 
dim_min_n  Finds the minimum of a variable's given dimensions at all other dimensions. 
dim_min_n_Wrap  Computes the minimum of a variable's given dimensions at all other dimensions and retains metadata. 
dim_num  Calculates the number of True values of a variable's rightmost dimension at all other dimensions. 
dim_num_n  Calculates the number of True values of a variable's given dimensions at all other dimensions. 
dim_numrun_n  Counts the number of "runs" (sequences) within a series containing zeros and ones. 
dim_pqsort  Computes the permutation vector generated by sorting the n  1th (rightmost) dimension. 
dim_pqsort_n  Computes the permutation vector generated by sorting the given dimension. 
dim_product  Computes the product of a variable's rightmost dimension at all other dimensions. 
dim_product_n  Computes the product of a variable's given dimension(s) at all other dimensions. 
dim_rmsd  Computes the rootmeansquaredifference between two variables' rightmost dimension at all other dimensions. 
dim_rmsd_n  Computes the rootmeansquaredifference between two variables' given dimensions at all other dimensions. 
dim_rmsd_n_Wrap  Computes the rootmeansquaredifference between two variables' given dimensions at all other dimensions. 
dim_rmsd_Wrap  Computes the rootmeansquaredifference between two variables' rightmost dimension at all other dimensions. 
dim_rmvmean  Calculates and removes the mean of the (rightmost) dimension at all other dimensions. 
dim_rmvmean_n  Calculates and removes the mean of the given dimension(s) at all other dimensions. 
dim_rmvmean_n_Wrap  Calculates and removes the mean of the given dimensions at all other dimensions and retains metadata. 
dim_rmvmean_Wrap  Calculates and removes the mean of the (rightmost) dimension at all other dimensions and retains metadata. 
dim_rmvmed  Calculates and removes the median of the (rightmost) dimension at all other dimensions. 
dim_rmvmed_n  Calculates and removes the median of the given dimension(s) at all other dimensions. 
dim_rmvmed_n_Wrap  Calculates and removes the median of the given dimensions at all other dimensions and retains metadata. 
dim_rmvmed_Wrap  Calculates and removes the median of the (rightmost) dimension at all other dimensions and retains metadata. 
dim_standardize  Calculates standardized anomalies of the rightmost dimension at all other dimensions. 
dim_standardize_n  Calculates standardized anomalies of the given dimension(s) at all other dimensions. 
dim_standardize_n_Wrap  Calculates standardized anomalies of the given dimensions at all other dimensions and retains metadata. 
dim_standardize_Wrap  Calculates standardized anomalies of the rightmost dimension at all other dimensions and retains metadata. 
dim_stat4  Computes the first four moments (average, variance, skewness, and kurtosis) of the rightmost dimension for all other dimensions. 
dim_stat4_n  Computes the first four moments (average, variance, skewness, and kurtosis) of the given dimension(s) for all other dimensions. 
dim_stddev  Computes the population standard deviation of a variable's rightmost dimension at all other dimensions. 
dim_stddev_n  Computes the population standard deviation of a variable's given dimension(s) at all other dimensions. 
dim_stddev_n_Wrap  Computes the population standard deviation of a variable's given dimension(s) at all other dimensions and retains metadata. 
dim_stddev_Wrap  Computes the population standard deviation of a variable's rightmost dimension at all other dimensions and retains metadata. 
dim_sum  Computes the arithmetic sum of a variable's rightmost dimension at all other dimensions. 
dim_sum_n  Computes the arithmetic sum of a variable's given dimension(s) at all other dimensions. 
dim_sum_n_Wrap  Computes the arithmetic sum of a variable's given dimensions at all other dimensions and retains metadata. 
dim_sum_wgt  Computes the weighted sum of a variable's rightmost dimension at all other dimensions. 
dim_sum_wgt_n  Computes the weighted sum of a variable's given dimension at all other dimensions. 
dim_sum_wgt_n_Wrap  Computes the weighted sum of a variable's given dimension at all other dimensions and retains metadata. 
dim_sum_wgt_Wrap  Computes the weighted sum of a variable's rightmost dimension at all other dimensions and retains metadata. 
dim_sum_Wrap  Computes the arithmetic sum of a variable's rightmost dimension at all other dimensions and retains metadata. 
dim_variance  Computes the unbiased estimates of the variance of a variable's rightmost dimension. 
dim_variance_n  Computes the unbiased estimates of the variance of a variable's given dimension(s) at all other dimensions. 
dim_variance_n_Wrap  Computes unbiased estimates of the variance of a variable's given dimension(s) at all other dimensions and retains metadata. 
dim_variance_Wrap  Computes unbiased estimates of the variance of a variable's rightmost dimension at all other dimensions and retains metadata. 
dtrend  Estimates and removes the least squares linear trend of the rightmost dimension from all grid points. 
dtrend_leftdim  Estimates and removes the least squares linear trend of the leftmost dimension from all grid points and retains meta data. 
dtrend_msg  Estimates and removes the least squares linear trend of the rightmost dimension from all grid points (missing values allowed). 
dtrend_msg_n  Estimates and removes the least squares linear trend of the dimth dimension from all grid points (missing values allowed). 
dtrend_n  Estimates and removes the least squares linear trend of the given dimension from all grid points. 
dtrend_quadratic  Estimates and removes the least squares quadratic trend of the rightmost dimension from all grid points. 
dtrend_quadratic_msg_n  Estimates and removes the least squares quadratic trend of the dimth dimension from all grid points (missing values allowed). 
equiv_sample_size  Estimates the number of independent values of a series of correlated observations. 
erf  Evaluates the real error function. 
erfc  Evaluates the real complementary error function. 
esacr  Computes sample autocorrelations 
esacv  Computes sample autocovariances 
esccr  Computes sample crosscorrelations. 
esccv  Computes sample crosscovariances. 
escorc  Computes sample crosscorrelations at lag 0 only. 
escorc_n  Computes sample crosscorrelations at lag 0 only, across the given dimensions. 
escovc  Computes sample crosscovariances at lag 0 only. 
exp  Computes the value of e (the base of natural logarithms) raised to the power of the input. 
ezfftb  Perform a Fourier synthesis from real and imaginary coefficients. 
ezfftf  Perform a Fourier analysis on a real periodic sequence. 
fabs  Computes the absolute value of numeric types. 
fft2db  Performs a twodimensional discrete backward Fourier transform (Fourier synthesis). 
fft2df  Performs a twodimensional forward real discrete Fourier transform (i.e., Fourier analysis) of a real periodic array. 
filwgts_lancos  Calculates onedimensional filter weights (deprecated). 
filwgts_lanczos  Calculates onedimensional filter weights. 
filwgts_normal  Calculates onedimensional filter weights based upon the normal (gaussian) distribution. 
floor  Computes the largest integer value smaller than the input. 
fourier_info  Performs fourier analysis on one or more periodic series. 
ftest  Applies Ftest for variances and returns an estimate of the statistical significance. 
gamma  Evaluates the complete gamma function. 
gammainc  Evaluates the incomplete gamma function. 
genNormalDist  Generates a normal distribution. 
inverse_matrix  Computes the inverse of a general matrix using LU factorization. 
kf_filter  Extract equatorial waves by filtering in the WheelerKiladis wavenumberfrequency domain. 
kolsm2_n  Use the KolmogorovSmirnov twosample test to determine if two samples are from the same distribution. 
kron_product  Computes the Kronecker product for twodimensional matrices. 
linrood_latwgt  Computes the latitudes and weights used by the LinRood Model. 
linrood_wgt  Computes the weights used by the LinRood Model. 
local_max  Determines the relative maxima for a 2dimensional array. 
local_min  Determines the relative minima for a 2dimensional array. 
log  Computes the natural log of a numeric type. 
log10  Computes the log base 10 of a numeric type. 
lspoly  Calculates a set of coefficients for a weighted least squares polynomial fit to the given data. 
lspoly_n  Calculates a set of coefficients for a weighted least squares polynomial fit to the given data on the given dimension. 
max  Computes the maximum value of a multidimensional array. 
min  Computes the minimum value of a multidimensional array. 
mod  Remainder function which emulates the fortran "mod" intrinsic function. 
NewCosWeight  Performs cosine of the latitude weighting on the given array. 
pattern_cor  Compute centered or uncentered pattern correlation. 
pdfx  Generates a univariate probability density distribution (PDF). 
pdfxy  Generates a joint probability density distribution. 
pdfxy_bin  Performs looping necessary to calculate the bivariate (joint) probability distribution (see pdfxy). 
product  Computes the product of the input. 
qsort  Sorts a singly dimensioned array. 
quadroots  Determine roots of a quadratic equation [ a*x^2 + b*x + c]. 
reg_multlin  Performs basic multiple linear regression analysis. 
reg_multlin_stats  Performs multiple linear regression analysis including confidence estimates and creates an ANOVA table. 
regcoef  Calculates the linear regression coefficient between two variables. 
regCoef  Calculates the linear regression coefficient between two variables. 
regCoef_n  Calculates the linear regression coefficient between two variables on the given dimensions. 
regline  Calculates the linear regression coefficient between two series. 
regline_stats  Performs simple linear regression including confidence estimates and creates an ANOVA table. 
rmInsufData  Sets all instances (i.e. time) of a grid point to missing if a userprescribed percentage of points is missing. 
round  Rounds a float or double variable to the nearest whole number. 
run_cor  Calculates a running correlation. 
runave  Calculates an unweighted running average on the rightmost dimension. 
runave_n  Calculates an unweighted running average on the given dimension. 
runave_n_Wrap  Calculates an unweighted running average on the given dimension and retains metadata. 
runave_Wrap  Calculates an unweighted running average on the rightmost dimension and retains metadata. 
sign_f90  Mimic the behavior of fortran90's sign transfer function. 
sign_matlab  Mimic the behavior of Matlab's sign function. 
simpeq  Integrates a sequence of equally spaced points using Simpson's Rule. 
simpne  Integrates a sequence of unequally spaced points using Simpson's threepoint formula. 
sin  Computes the sine of numeric types. 
sindex_yrmo  Calculates the Southern Oscillation Index given two series of yearmonth values. 
sinh  Computes the hyperbolic sine of numeric types. 
smth9  Performs nine point local smoothing on one or more 2D grids. 
smth9_Wrap  Performs nine point local smoothing on one or more 2D grids and retains metadata. 
snindex_yrmo  Calculates the Southern Oscillation Index and the noise index given two series of yearmonth values. 
solve_linsys  Computes the solution to a real system of linear equations. 
sparse_matrix_mult  Multiples a sparse matrix with a dense matrix. Function under construction. Calling arguments may change. 
spcorr  Computes Spearman rank order correlation coefficient. 
spcorr_n  Computes Spearman rank order correlation coefficient across the given dimension. 
specx_anal  Calculates spectra of a series. 
specx_ci  Calculates the theoretical Markov spectrum and the lower and upper confidence curves. 
specxy_anal  Calculates cross spectra quantities of a series. 
sqrt  Computes the square root of its input. 
SqrtCosWeight  Performs squareroot of the cosine of the latitude weighting on the given array. 
sqsort  Sorts a singly dimensioned arrays of strings. 
stat2  Calculates the first two moments of the given input. 
stat4  Calculates estimates of the first four moments (mean, variance, skewness, and kurtosis) of the given input. 
stat_dispersion  Computes a number of robust statistics. 
stat_medrng  Calculates median, range, and midrange of the given input. 
stat_trim  Calculates trimmed estimates of the first two moments of the given input. 
stddev  Calculates the sample standard deviation. 
student_t  Calculates the twotailed probability of the Studentt distribution. 
sum  Sums the input. 
tan  Computes the tangent of numeric types. 
tanh  Computes the hyperbolic tangent of numeric types. 
taper  Applies splitcosinebell tapering to one or more series across the rightmost dimension. 
taper_n  Applies splitcosinebell tapering to one or more series across the given dimension. 
trend_manken_n  MannKendall nonparametric test for monotonic trend plus the TheilSen robust estimate of linear trend. 
ttest  Returns an estimate of the statistical significance and, optionally, the tvalues. 
variance  Computes an unbiased estimate the variance of all input points. 
wave_number_spc  Computes the total power spectrum as a function of latitudinal wave number. 
wavelet  Calculates the wavelet transform of a time series and significance levels. 
wavelet_default  Calculates the wavelet transform of a time series and significance levels. 
wgt_area_smooth  Smooths an array of data using a 5point 2D areaweighted smoothing algorithm. 
wgt_areaave  Calculates the area average of a quantity using weights. 
wgt_areaave2  Calculates the area average of a quantity using twodimensional weights. 
wgt_areaave_Wrap  Calculates the area average of a quantity using weights and retains metadata. 
wgt_arearmse  Calculates a weighted area rootmeansquaredifference between two variables. 
wgt_arearmse2  Calculates a weighted area rootmeansquaredifference (rmse) between two variables using twodimensional weights. 
wgt_areasum2  Calculates the area sum (total) of a quantity using twodimensional weights. 
wgt_runave  Calculates a weighted running average across the rightmost dimension. 
wgt_runave_leftdim  Calculate a weighted running average over the leftmost dimenaion (usually, "time") and return in the original order with meta data. 
wgt_runave_n  Calculates a weighted running average across the given dimension. 
wgt_runave_n_Wrap  Calculates a weighted running average on the given dimension and retains metadata. 
wgt_runave_Wrap  Calculates a weighted running average on the rightmost dimension and retains metadata. 
wgt_volave  Calculates the volume average of a quantity using weights. 
wgt_volave_ccm  Calculates the volume average of a quantity from the CCM using weights. 
wgt_volrmse  Calculates a weighted volume rootmeansquaredifference between two variables. 
wgt_volrmse_ccm  Calculates a weighted volume rootmeansquaredifference between two variables from the CCM. 
wk_smooth121  Performs a specialized 121 filter for WheelerKiladis plots. 
zonalAve  Computes a zonal average of the input array. 
Graphics routines
boxplot  Creates a boxplot. 
ColorNegDashZeroPosContour  Sets the negative contours to dashed, and colors the negative, positive, and zero contours to userspecified colors. 
ColorShadeLeGeContour 
Shades contour regions given low and high values and two colors. (Superceded by gsn_contour_shade as of version 4.3.0.) 
create_graphic  Creates a graphic object 
draw  Draws the given graphical objects. 
drawNDCGrid  Draws NDC grid lines at 0.1 NDC coordinate intervals and labels them. 
get_isolines  Retrieves the points that define a contour line. 
gsn_add_annotation  Attaches the given annotation to the given plot. 
gsn_add_polygon  Attaches a filled polygon to the given plot. 
gsn_add_polyline  Attaches a polyline to the given plot. 
gsn_add_polymarker  Attaches polymarkers to the given plot. 
gsn_add_shapefile_polygons  Attaches shapefile polygon data to the given plot(s) using randomlyfilled polygons. 
gsn_add_shapefile_polylines  Attaches shapefile polyline or polygon data to the given plot(s) using polylines. 
gsn_add_shapefile_polymarkers  Attaches shapefile point data to the given plot(s) using polymarkers. 
gsn_add_text  Attaches text strings to the given plot. 
gsn_attach_plots  Attaches a series of plots to a base plot. 
gsn_blank_plot  Draws a blank plot with tickmarks pointing inward. 
gsn_contour  Creates and draws a contour plot. 
gsn_contour_map  Creates and draws a contour plot over a map. 
gsn_contour_shade  Shades contour regions given low and/or high values using colors or patterns. 
gsn_coordinates  Draws or attaches the data coordinate locations on the given plot as grid lines or markers. 
gsn_create_labelbar  Creates a labelbar. 
gsn_create_legend  Creates a legend. 
gsn_create_text  Creates text strings. 
gsn_csm_attach_zonal_means  Attaches a zonal means plot to a contour/map plot. 
gsn_csm_blank_plot  Draws a blank plot with tickmarks pointing outward. 
gsn_csm_contour  Creates and draws a contour plot. 
gsn_csm_contour_map  Creates and draws a contour plot over a map. 
gsn_csm_contour_map_ce  Creates and draws a contour plot over a cylindrical equidistant map. 
gsn_csm_contour_map_overlay  Creates and draws two contour plots over a map. 
gsn_csm_contour_map_polar  Creates and draws a contour plot over a polar stereographic map. 
gsn_csm_hov  Creates and draws a Hovmueller (time v.s. longitude) plot. 
gsn_csm_lat_time  Creates and draws a latitude versus time plot. 
gsn_csm_map  Creates and draws a map. 
gsn_csm_map_ce  Creates and draws a cylindrical equidistant map. 
gsn_csm_map_polar  Creates and draws a polar stereographic map. 
gsn_csm_pres_hgt  Creates and draws a pressure/height plot. 
gsn_csm_pres_hgt_streamline  Creates and draws a pressure/height contour plot overlaid with streamlines. 
gsn_csm_pres_hgt_vector  Creates and draws a pressure/height contour plot overlaid with vectors. 
gsn_csm_streamline  Creates and draws a streamline plot. 
gsn_csm_streamline_contour_map  Creates and draws streamlines over a contour plot over a map. 
gsn_csm_streamline_contour_map_ce  Creates and draws streamlines over a contour plot over a cylindrical equidistant map. 
gsn_csm_streamline_contour_map_polar  Creates and draws streamlines over a contour plot over a polar stereographic map. 
gsn_csm_streamline_map  Creates and draws a streamline plot over a map. 
gsn_csm_streamline_map_ce  Creates and draws a streamline plot over a cylindrical equidistant map. 
gsn_csm_streamline_map_polar  Creates and draws a streamline plot over a polar stereographic map. 
gsn_csm_time_lat  Creates and draws a time versus latitude plot. 
gsn_csm_vector  Creates and draws a vector plot. 
gsn_csm_vector_map  Creates and draws a vector plot over a map. 
gsn_csm_vector_map_ce  Creates and draws a vector plot over a cylindrical equidistant map. 
gsn_csm_vector_map_polar  Creates and draws a vector plot over a polar stereographic map. 
gsn_csm_vector_scalar  Creates and draws a vector plot, and uses a scalar field to draw a separate contour plot or color the vectors. 
gsn_csm_vector_scalar_map  Creates and draws a vector plot over a map, and uses a scalar field to draw a separate contour plot or color the vectors. 
gsn_csm_vector_scalar_map_ce  Creates and draws a vector plot over a cylindrical equidistant map projection, and uses a scalar field to draw a separate contour plot or color the vectors. 
gsn_csm_vector_scalar_map_polar  Creates and draws a vector plot over a polar stereographic map projection, and uses a scalar field to draw a separate contour plot or color the vectors. 
gsn_csm_x2y  Creates and draws an XY plot with two different X axes. 
gsn_csm_x2y2  Creates and draws an XY plot with two different X and Y axes 
gsn_csm_xy  Creates and draws an XY plot. 
gsn_csm_xy2  Creates and draws an XY plot with two different Y axes. 
gsn_csm_xy3  Creates and draws an XY plot with three different Y axes. 
gsn_csm_y  Creates and draws an XY plot, using index values for the X axis. 
gsn_histogram  Draws a histogram plot on the given workstation. 
gsn_labelbar_ndc  Draws a labelbar on the given workstation. 
gsn_legend_ndc  Draws a legend on the given workstation. 
gsn_map  Creates and draws a map. 
gsn_open_wks  Opens a workstation on which to draw graphics. 
gsn_panel  Draws multiple plots of identical size on a single frame. 
gsn_polygon  Draws a filled polygon on the given plot. 
gsn_polygon_ndc  Draws a filled polygon on the given workstation. 
gsn_polyline  Draws a polyline on the given plot. 
gsn_polyline_ndc  Draws a polyline on the given workstation. 
gsn_polymarker  Draws polymarkers on the given plot. 
gsn_polymarker_ndc  Draws polymarkers on the given workstation. 
gsn_streamline  Creates and draws a streamline plot. 
gsn_streamline_map  Creates and draws a streamline plot over a map. 
gsn_streamline_scalar  Creates and draws a streamline plot colored by a given a scalar field. 
gsn_streamline_scalar_map  Creates and draws a streamline plot over a map, and colors the streamlines using the given scalar field. 
gsn_table  Draws a table with text. 
gsn_text  Draws text strings on the given plot. 
gsn_text_ndc  Draws text strings on the given workstation. 
gsn_vector  Creates and draws a vector plot. 
gsn_vector_map  Creates and draws a vector plot over a map. 
gsn_vector_scalar  Creates and draws a vector plot colored by a given a scalar field. 
gsn_vector_scalar_map  Creates and draws a vector plot over a map, and colors the vectors using the given scalar field. 
gsn_xy  Creates and draws an XY plot. 
gsn_y  Creates and draws an XY plot, using index values for the X axis. 
infoTimeStamp  Draws two text strings at the bottom of the workstation to indicate the time the plot was created and other information. 
maximize_output  Maximizes the sizes of a series of plots drawn in a single frame. 
msgValOutline  Draws an outline around missing data in vector and streamline plots. 
ngezlogo  Draws the NCAR logo in the lower right corner of the given workstation. 
nggetp  Retrieves values for various parameters for the NCAR ngezlogo procedure. 
nglogo  Draws various NCAR and UCAR logos on the given workstation. 
ngsetp  Sets values for various parameters for the NCAR ngezlogo procedure. 
NhlAddAnnotation  Add annotations to a plot object as an external annotation. 
NhlAddOverlay  Overlays one plot object on another. 
NhlAddPrimitive  Adds a Primitive object to an existing plot. 
NhlDataPolygon  Draws a polygon using data coordinates. 
NhlDataPolyline  Draws a polyline using data coordinates. 
NhlDataPolymarker  Draws polymarkers using data coordinates. 
NhlDraw  Draws the given graphical objects. 
NhlNDCPolygon  Draws a polygon using NDC coordinates. 
NhlNDCPolyline  Draws a polyline using NDC coordinates. 
NhlNDCPolymarker  Draws polymarkers using NDC coordinates. 
NhlNewDashPattern  Adds new dash patterns to the existing table of dash patterns. 
NhlNewMarker  Adds new markers to the existing table of markers. 
NhlRemoveAnnotation  Remove annotations from the plot they are registered in. 
NhlRemoveOverlay  Removes one or more plots from an overlay. 
NhlRemovePrimitive  Removes one or more primitives from the given Transform object. 
NhlSetDashPattern  Sets the dash patterns for a given list of dash pattern indexes and workstations. 
NhlSetMarker  Sets the markers for a given list of marker indexes and workstations. 
overlay  Overlays one plot object on another. 
paleo_outline  Creates continental outlines from model orography data. 
pie_chart  Creates a basic pie chart. 
reset_device_coordinates  Resets the PS/PDF device coordinates back to their default values. 
setColorContourClear  Sets the color contours between two given levels transparent. 
ShadeCOI  Adds the cone of influence as a shaded polygon. 
ShadeGeLeContour 
Shades contour regions given low and high values and a shade pattern. (Superceded by gsn_contour_shade as of version 4.3.0.) 
ShadeGtContour 
Shades contour regions above a given value with the given fill pattern. (Superceded by gsn_contour_shade as of version 4.3.0.) 
ShadeLtContour 
Shades contour regions below a given value with the given fill pattern. (Superceded by gsn_contour_shade as of version 4.3.0.) 
ShadeLtGtContour 
Shades contour regions below a given value and above a given value with the specified fill patterns. (Superceded by gsn_contour_shade as of version 4.3.0.) 
skewT_BackGround  Creates a background chart for Skew T, Log P plotting. 
skewT_PlotData  Plot a sounding and (optionally) winds on Skew T, Log P charts created by skewT_BackGround. 
symMinMaxPlt  Calculates the minimum/maximum values for a variable and uses nice_mnmxintvl to calculate the symmetric contour interval. 
tdclrs  Defines a set of colors for use with selected TDPACK routines. 
tdctri  Cuts the triangles in a triangle list with a plane perpendicular to an axis (for use with selected TDPACK routines). 
tdcudp  Not yet implemented. 
tdcurv  Draws the projection of a curve defined by an array of points in 3space. 
tddtri  Draws triangles defined by a triangle list (for use with selected TDPACK routines). 
tdez2d  Draws a surface on the specified workstation. 
tdez3d  Draws an isosurface on the specified workstation. 
tdgetp  Retrieves TDPACK parameter values. 
tdgrds  Draws perimeters, ticks, and grid lines on the six sides of a box (for use with selected TDPACK routines). 
tdgrid  Draws a grid on a particular face of a box in 3space (for use with selected TDPACK routines). 
tdgtrs  Gets the definition of a specified rendering style (for use with selected TDPACK routines). 
tdinit  Defines eye position, line of sight, up direction, and stereo flag for selected TDPACK routines. 
tditri  Adds triangles defining an isosurface to a triangle list (for use with selected TDPACK routines). 
tdlbla  Draws labels for a particular face of a box in 3space (for use with selected TDPACK routines). 
tdlblp  Not yet implemented. 
tdlbls  Draws labels for all faces of a box in 3space (for use with selected TDPACK routines). 
tdline  Draws the projection of a solid line in 3space (for use with selected TDPACK routines). 
tdlndp  Not yet implemented. 
tdlnpa  Draws the projection of a line joining two points in the reference parallelogram (for use with selected TDPACK routines). 
tdlpdp  Not yet implemented. 
tdmtri  Adds triangles defining a 3D marker to a triangle list for use with selected TDPACK routines. 
tdotri  Orders the triangles in a triangle list for proper rendering (for use with selected TDPACK routines). 
tdpara  Defines the reference parallelogram for use with selected TDPACK routines. 
tdplch  Draws a string in the plane of the reference parallelogram (for use with selected TDPACK routines). 
tdprpa  Retrieves the coordinates of a projection in the projection plane, given the parallelogram coordinates of a point (for use with selected TDPACK routines). 
tdprpi  Retrieves the parallelogram coordinates of a point in the reference parallelogram, given a point in the projection plane (for use with selected TDPACK routines.) 
tdprpt  Retrieves the coordinates of its projection in the projection plane, given the coordinates of a point in 3space (for use with selected TDPACK routines). 
tdsetp  Sets TDPACK parameter values. 
tdsort  Sorts an array (for use with selected TDPACK routines). 
tdstri  Adds triangles defining a simple surface to a triangle list (for use with selected TDPACK routines). 
tdstrs  Sets the values defining a selected rendering style (for use with selected TDPACK routines). 
tdttri  Adds triangles defining a trajectory to a triangle list (for use with selected TDPACK routines). 
WindRoseBasic  Plots a basic wind rose. 
WindRoseColor  Plot a wind rose diagram where different colors are used to differentiate speed ranges. 
WindRoseThickLine  Plot a black and white wind rose diagram where different line thicknesses are used to differentiate speed ranges. 
wmbarb  Draws wind barbs on the given workstation. 
wmbarbmap  Draws wind barbs over maps. 
wmdrft  Draws weather front lines on the given workstation. 
wmgetp  Retrieves parameter values for selected Wmap routines. 
wmlabs  Plots special symbols and icons for daily weather. 
wmsetp  Sets parameter values for selected Wmap routines. 
wmstnm  Plots station model data on the given workstation. 
wmvect  Draws vectors on the given workstation. 
wmvectmap  Draws vectors over maps. 
wmvlbl  Draws an informational label box for plots produced by wmvect or wmvectmap. 
wrf_contour  Creates a contour plot from ARW WRF model output. 
wrf_map  Creates a map background for ARW WRF model data. 
wrf_map_overlay  Overlays different plot id's over a map background (deprecated in version 5.1.0). 
wrf_map_overlays  Overlays different contour and vector plots over a WRFARW map background. 
wrf_map_resources  Sets map plotting resources based on an input WRFARW file. 
wrf_map_zoom  Zooms into a portion of the ARW WRF model domain, and creates a map background (deprecated in version 5.1.0). 
wrf_overlay  Overlays multiple plots, created from other ARW WRF plot functions (deprecated in version 5.1.0). 
wrf_overlays  Overlays multiple plots, created from other ARW WRF plot functions. 
wrf_vector  Creates a vector plot from ARW WRF model output. 
Group creators
filegrpdef  Defines a list of group (names), for a supported file, or group. 
Group query
getfilegrpnames  Returns an array of file group names in the specified supported file. 
Interpolation
area_conserve_remap  Performs areal conservative remapping from one rectilinear grid to another. 
area_conserve_remap_Wrap  Performs areal conservative remapping from one rectilinear grid to another and preserves meta data. 
area_hi2lores  Interpolates from high resolution rectilinear grids to low resolution recitlinear grids using local area averaging. 
area_hi2lores_Wrap  Interpolates from high resolution rectilinear grids to low resolution rectilinear grids using local area averaging. (retains meta data) 
bin_avg  Calculates gridded binned averages and counts using randomly spaced data. 
csa1  Calculates an approximating cubic spline for the input data, one 1dimensional section at a time. 
csa1d  Calculates an approximating cubic spline for the input data, one 1dimensional section at a time. 
csa1s  Calculates an approximating cubic spline for the input data, one 1dimensional section at a time. 
csa1x  Calculates an approximating cubic spline for the input data, one 1dimensional section at a time. 
csa1xd  Calculates an approximating cubic spline for the input data, one 1dimensional section at a time. 
csa1xs  Calculates an approximating cubic spline for the input data, one 1dimensional section at a time. 
csa2  Calculates an approximating cubic spline for twodimensional input data. 
csa2d  Calculates an approximating cubic spline for twodimensional input data. 
csa2l  Calculates an approximating cubic spline for twodimensional input data. 
csa2ld  Calculates an approximating cubic spline for twodimensional input data. 
csa2ls  Calculates an approximating cubic spline for twodimensional input data. 
csa2lx  Calculates an approximating cubic spline for twodimensional input data. 
csa2lxd  Calculates an approximating cubic spline for twodimensional input data. 
csa2lxs  Calculates an approximating cubic spline for twodimensional input data. 
csa2s  Calculates an approximating cubic spline for twodimensional input data. 
csa2x  Calculates an approximating cubic spline for twodimensional input data. 
csa2xd  Calculates an approximating cubic spline for twodimensional input data. 
csa2xs  Calculates an approximating cubic spline for twodimensional input data. 
csa3  Calculates an approximating cubic spline for threedimensional input data. 
csa3d  Calculates an approximating cubic spline for threedimensional input data. 
csa3l  Calculates an approximating cubic spline for threedimensional input data. 
csa3ld  Calculates an approximating cubic spline for threedimensional input data. 
csa3ls  Calculates an approximating cubic spline for threedimensional input data. 
csa3lx  Calculates an approximating cubic spline for threedimensional input data. 
csa3lxd  Calculates an approximating cubic spline for threedimensional input data. 
csa3lxs  Calculates an approximating cubic spline for threedimensional input data. 
csa3s  Calculates an approximating cubic spline for threedimensional input data. 
csa3x  Calculates an approximating cubic spline for threedimensional input data. 
csa3xd  Calculates an approximating cubic spline for threedimensional input data. 
csa3xs  Calculates an approximating cubic spline for threedimensional input data. 
csc2s  Converts Cartesian coordinates on a unit sphere to spherical coordinates (lat/lon). 
csgetp  Retrieves control parameters for Cssgrid routines. 
css2c  Converts spherical coordinates (lat/lon) to Cartesian coordinates on a unit sphere. 
cssetp  Sets control parameters for Cssgrid routines. 
cssgrid  Uses tension splines to interpolate unstructured (randomlyspaced) data on a unit sphere to data values on a rectilinear grid. 
cssgrid_Wrap  Uses tension splines to interpolate unstructrued (randomlyspaced) data on a unit sphere to data values on a rectilinear grid (retains metadata). 
csstri  Calculates a Delaunay triangulation of data randomly positioned on the surface of a sphere. 
csvoro  Determines Voronoi polygons for data randomly positioned on a sphere and returns vertices for the one surrounding a specified input point. 
curvilinear_to_SCRIP  Writes the description of a curvilinear grid to a SCRIP file. 
dsgetp  Gets parameters for Dsgrid routines. 
dsgrid2  Interpolates data from an unstructured (randomlyspaced) grid to a rectilinear grid using inverse distance weighted interpolation. 
dsgrid2d  Interpolates double data from an unstructured (randomlyspaced) grid to a rectilinear grid using inverse distance weighted interpolation. (Deprecated version.) 
dsgrid2s  Interpolates float data from an unstructured (randomlyspaced) grid to a rectilinear grid using inverse distance weighted interpolation. (Deprecated version.) 
dsgrid3  Interpolates float data from an unstructured (randomlyspaced) grid to a 3D grid using inverse distance weighted interpolation. 
dsgrid3d  Interpolates double data from an unstructured (randomlyspaced) grid to a 3D grid using inverse distance weighted interpolation. (Deprecated version.) 
dsgrid3s  Interpolates float data from an unstructured (randomlyspaced) grid to a 3D grid using inverse distance weighted interpolation. (Deprecated version.) 
dspnt2  Interpolates 2D data at specified points. 
dspnt2d  Interpolates 2D data at specified points. (Deprecated version.) 
dspnt2s  Interpolates 2D float data at specified points. (Deprecated version.) 
dspnt3  Interpolates 3D data at specified points. 
dspnt3d  Interpolates 3D double data at specified points. (Deprecated version.) 
dspnt3s  Interpolates 3D float data at specified points. (Deprecated version.) 
dssetp  Sets parameters for Dsgrid routines. 
ESMF_regrid  Regrids data from one lat/lon grid to another, using ESMF software. 
ESMF_regrid_gen_weights  Writes a weight file using the offline ESMF weight generator. 
ESMF_regrid_with_weights  Using the provided weight file, regrids data from one lat/lon grid to another. 
ftcurv  Calculates an interpolatory spline through a sequence of functional values. 
ftcurvd  Calculates the derivatives of an interpolatory spline under tension. 
ftcurvi  Calculates integrals of an interpolatory spline under tension between two userspecified limits. 
ftcurvp  Calculates an interpolatory spline under tension through a sequence of functional values for a periodic function. 
ftcurvpi  Calculates an integral of an interpolatory spline between two specified points. 
ftcurvps  Calculates a smoothing spline. 
ftcurvs  Calculates a smoothing spline. 
ftgetp  Retrieves control parameters for Fitgrid routines. 
ftkurv  Calculates an interpolatory spline for parametric curves. 
ftkurvd  Calculates an interpolatory spline for parametric curves; it also calculates first and second derivatives of the interpolatory spline. 
ftkurvp  Calculates an interpolatory spline under tension through a sequence of points in the plane forming a closed curve. 
ftkurvpd  Calculates an interpolatory spline for closed parametric curves; it also calculates first and second derivatives of the interpolatory spline. 
ftsetp  Sets control parameters for Fitgrid routines. 
idsfft  Interpolates 2D random data. 
int2p  Interpolates pressure levels to a different set of pressure levels. 
int2p_n  Interpolates pressure levels to a different set of pressure levels on the given dimension. 
int2p_n_Wrap  Interpolates pressure levels to a different set of pressure levels and returns meta data. 
int2p_Wrap  Interpolates pressure levels to a different set of pressure levels and returns meta data. 
latlon_to_SCRIP  Writes the description of a lat/lon grid to a SCRIP file. 
linint1  Interpolates from one series to another using piecewise linear interpolation across the rightmost dimension. 
linint1_n  Interpolates from one series to another using piecewise linear interpolation across the given dimension. 
linint1_n_Wrap  Interpolates from one series to another using piecewise linear interpolation across the given dimension, and retains metadata. 
linint1_Wrap  Interpolates from one series to another using piecewise linear interpolation, and retains metadata. 
linint2  Interpolates from a rectilinear grid to another rectilinear grid using bilinear interpolation. 
linint2_points  Interpolates from a rectilinear grid to an unstructured grid using bilinear interpolation. 
linmsg  Linearly interpolates to fill in missing values. 
linmsg_n  Linearly interpolates to fill in missing values, given the dimension to do the interpolation across. 
natgrid  Interpolates data from an unstructured (randomlyspaced) grid to a rectilinear grid using natural neighbor interpolation. 
natgrid_Wrap  Interpolates data from an unstructured (randomlyspaced) grid to a rectilinear grid using natural neighbor interpolation and retains metadata. 
natgridd  Interpolates double data on an unstructured grid to a rectilinear grid. (Deprecated version.) 
natgrids  Interpolates float data on an unstructured grid to a rectilinear grid. (Deprecated version.) 
nngetaspectd  Retrieves an aspect at a specified coordinate position. 
nngetaspects  Retrieves an aspect at a specified coordinate position. 
nngetp  Retrieves control parameters for Natgrid routines. 
nngetsloped  Retrieves a slope at a specified coordinate position. 
nngetslopes  Retrieves a slope at a specified coordinate position. 
nngetwts  Retrieves natural neighbors and weights for the function values at those neighbors. 
nngetwtsd  Retrieves natural neighbors and weights for the function values at those neighbors. 
nnpnt  Interpolates from 2D random data to get values at a specified set of points. 
nnpntd  Interpolates from 2D random double data to get values at a specified set of points. (Deprecated version.) 
nnpntend  Terminates interpolation from 2D random data to get values at a specified set of points. 
nnpntendd  Terminates interpolation from 2D random data to get values at a specified set of points. 
nnpntinit  Initializes internal quantities, for given input data, to allow subsequent nnpnt calls to interpolate at specified points. 
nnpntinitd  Initializes internal quantities, for given input data, to allow subsequent nnpntd calls to interpolate at specified points. 
nnpntinits  Initializes internal quantities, for given input data, to allow subsequent nnpnts calls to interpolate at specified points. 
nnpnts  Interpolates from 2D random float data to get values at a specified set of points. (Deprecated version.) 
nnsetp  Sets control parameters for Natgrid routines. 
obj_anal_ic  Iterative improvement objective analysis. 
obj_anal_ic_deprecated  Iterative correction objective analysis (Cressman, Barnes). 
obj_anal_ic_Wrap  Iterative improvement objective analysis and returns meta data. 
poisson_grid_fill  Replaces all missing (_FillValue) values in a grid with values derived from solving Poisson's equation via relaxation. 
rcm2points  Interpolates data on a curvilinear grid (i.e. RCM, WRF, NARR) to an unstructured grid. 
rcm2rgrid  Interpolates data on a curvilinear grid (i.e. RCM, WRF, NARR) to a rectilinear grid. 
rectilinear_to_SCRIP  Writes the description of a rectilinear grid to a SCRIP file. 
rgrid2rcm  Interpolates data on a rectilinear lat/lon grid to a curvilinear grid like those used by the RCM, WRF and NARR models/datasets. 
shgetnp  Finds the nearest point, or points (in a specified set of points), to a given point in 3space. 
shgetp  Retrieves control parameters for Shgrid routines. 
shgrid  Interpolates data from an unstructured grid to a grid in 3space. 
shsetp  Sets control parameters for Shgrid routines. 
sigma2hybrid  Interpolates from sigma to hybrid coordinates. 
trop_wmo  Determines the level of the thermal tropopause. 
unstructured_to_ESMF  Writes the description of an unstructured grid to an ESMF file. 
wrf_interp_1d  Linearly interpolates a onedimensional variable in the vertical. 
wrf_interp_2d_xy  Extracts a cross section from a given input field. 
wrf_interp_3d_z  Interpolates to a specified pressure/height level. 
wrf_user_intrp2d  Interpolates ARW WRF 2D model data along a give line. 
wrf_user_intrp3d  Interpolates ARW WRF model data vertically or horizontally. 
wrf_user_unstagger  Unstaggers an input variable along a specified dimension. 
Lat/lon functions
add90LatX  Adds two fake pole points (90S and 90N) to the rightmost dimension of the given data. 
add90LatY  Adds two fake pole points (90S and 90N) to the leftmost dimension of the given data. 
area_poly_sphere  Calculates the area enclosed by an arbitrary polygon on the sphere. 
bin_avg  Calculates gridded binned averages and counts using randomly spaced data. 
bin_sum  Calculates binned sums and counts over multiple invocations of the procedure. 
gaus  Computes gaussian latitudes and weights. 
gaus_lobat  Computes gaussian latitudes and weights using GaussLobatto quadrature. 
gaus_lobat_wgt  Computes GaussLobatto weights given a onedimensional array of GaussLobatto latitudes. 
gc_aangle  Finds the acute angle between two great circles on the globe. 
gc_clkwise  Tests clockwise/counterclockwise ordering of points on spherical polygon. 
gc_dangle  Finds the directed angle between two great circles having a specified intersection point. 
gc_inout  Determines if a list of lat/lon specified points are inside or outside of spherical lat/lon polygon(s). 
gc_latlon  Finds the great circle distance (true surface distance) between two points on the globe and interpolates points along the great circle. 
gc_onarc  Determines if a point on the globe lies on a specified great circle arc. 
gc_pnt2gc  Finds the angular distance from a point to a great circle. 
gc_qarea  Finds the area of a quadrilateral patch on the unit sphere. 
gc_tarea  Finds the area of a triangular patch on the unit sphere. 
getind_latlon2d  Finds the indices (subscripts) of twodimensional latitude/longitude arrays closest to a user specified latitude/longitude coordinate pair. 
landsea_mask  Returns a grid that contains a land sea mask given any latitude and longitude array. 
latGau  Generates gaussian latitudes and associated metadata. 
latGauWgt  Generates gaussian weights and associated metadata. 
latGlobeF  Generates latitudes and associated metadata for a global fixed grid. 
latGlobeFo  Generates latitudes and associated metadata for a global fixed offset grid. 
latlon2utm  Converts from lat/lon to UTM using a specified datum. 
latRegWgt  Generates [sin(lat+dlat/2)sin(latdlat/2) weights for equally spaced (regular) global grids that will sum to 2.0. 
lonFlip  Reorders an array about the central longitude coordinate variable (rectilinear grids only). 
lonGlobeF  Generates longitudes and associated metadata for a global fixed grid. 
lonGlobeFo  Generates longitudes and associated metadata for a global fixed offset grid. 
lonPivot  Pivots about a user specified longitude (rectilinear grids only). 
nggcog  Calculates the latitudes and longitudes of a set of points approximating a circle at a given point on the surface of the globe. 
niceLatLon2D  Check two dimensional map coordinates to see if they have a "nice" structure. 
NormCosWgtGlobe  Create normalized cosine weights that sum to 2.0. 
plt_pdfxy  Creates a nice plot of the joint probability array created by the pdfxy function. 
region_ind  Returns the indices (subscripts) of twodimensional latitude/longitude arrays that span user specified latitude/longitude boundaries. 
utm2latlon  Converts from UTM to lat/lon using a specified datum. 
wrf_ij_to_ll  Finds the nearest longitude, latitude locations to the specified model grid indices (i,j). 
wrf_latlon_to_ij  Finds the nearest model grid indices (i,j) to the specific location(s) in latitude and longitude (deprecated). 
wrf_ll_to_ij  Finds the nearest model grid indices (i,j) to the specified location(s) in longitude and latitude. 
wrf_user_ij_to_ll  Finds the nearest longitude, latitude locations to the specified model grid indices (i,j). 
wrf_user_ll_to_ij  Finds the nearest model grid indices (i,j) to the specified location(s) in longitude and latitude. 
Metadata routines
assignFillValue  Transfers the _FillValue attribute from one variable to another. 
copy_VarAtts  Copies all of a variable's attributes from one variable to another. 
copy_VarCoords  Copies all named dimensions and coordinate variables from one variable to another. 
copy_VarCoords_1  Copies all named dimensions and coordinate variables from one variable to another except for the rightmost dimension. 
copy_VarCoords_2  Copies all named dimensions and coordinate variables from one variable to another except for the rightmost two dimensions. 
copy_VarMeta  Copies all attributes, named dimensions and coordinate variables from one variable to another. 
copyatt  Copies all attributes, named dimensions and coordinate variables from one variable to another (deprecated version). 
default_fillvalue  Returns the default missing value for the given variable type. 
delete_VarAtts  Deletes one or more attributes associated with a variable. 
getFillValue  Retrieves the _FillValue of a variable, if present. 
getvaratts  Returns a list of attribute names for the given variable or file pointer. 
getVarDimNames  Retrieves dimension names for a variable in memory (deprecated version). 
getvardims  Returns a list of dimension names for the given variable. 
getVarFillValue  Retrieves the missing value of a variable, otherwise, it returns the default _FillValue. 
isatt  Returns logical values indicating whether the given attributes are attached to the given variable. 
iscoord  Returns True for every input string that is a coordinate variables of the given variable. 
isdim  Returns True if variable dimensions are defined in the given variable. 
isdimnamed  Returns True if variable dimensions have names in given variable. 
ismissing  Returns True for every element of the input that contains a missing value. 
isunlimited  Returns True if the given dimension name is defined as unlimited on the given file. 
nameDim  Assigns given named dimensions, long_name, and units to the input variable. 
set_default_fillvalue  Sets the default missing value for the given variable type. 
Meteorology
angmom_atm  Calculates the atmosphere's relative angular momentum. 
dewtemp_trh  Calculates the dew point temperature given temperature and relative humidity. 
fluxEddy  Calculates time averaged eddy flux quantities. 
hydro  Computes geopotential height using the hydrostatic equation. 
hyi2hyo  Interpolates from data on one set of hybrid levels to another set of hybrid levels. 
hyi2hyo_Wrap  Interpolates from data on one set of hybrid levels to another set of hybrid levels and preserves metadata. 
kf_filter  Extract equatorial waves by filtering in the WheelerKiladis wavenumberfrequency domain. 
lclvl  Calculates the pressure of the lifting condensation level. 
mixhum_ptd  Calculates the mixing ratio or specific humidity given pressure and dew point temperature. 
mixhum_ptrh  Calculates the mixing ratio or specific humidity given pressure, temperature and relative humidity. 
omega_to_w  Convert omega vertical velocity (Pa/s) to (m/s). 
prcwater_dp  Computes column precipitable water of the rightmost dimension. 
pres2hybrid  Interpolates data on constant pressure levels to hybrid levels. 
pres2hybrid_Wrap  Interpolates data on constant pressure levels to hybrid levels and retains metadata. 
pres_sigma  Calculates the pressure at specified sigma levels. 
pslec  Computes sea level pressure from CCM/CAM hybrid model variables using the ECMWF formulation. 
pslhor  Computes sea level pressure from CCM/CAM hybrid model variables using the ECMWF formulation and Trenberth's horizontal correction. 
pslhyp  Computes sea level pressure using the hypsometric equation. 
rdsstoi  Reads weekly/monthly compocp site and climatology grids. 
relhum  Calculates relative humidity given temperature, mixing ratio, and pressure. 
relhum_ttd  Calculates relative humidity given temperature and dew point temperature. 
stdatmus_p2tdz  Calculates the corresponding temperature, density, and height based on the 1976 U.S. standard atmosphere, given the pressure. 
stdatmus_z2tdp  Calculates the corresponding temperature, density, and pressure based on the 1976 U.S. standard atmosphere, given the height. 
uv2dv_cfd  Computes divergence using centered finite differences. 
uv2vr_cfd  Computes relative vorticity using centered finite differences. 
vibeta  Performs vertical integration using beta factors. 
w_to_omega  Convert vertical velocity with units (m/s) to Pa/s. 
wind_component  Calculate zonal and meridional wind components from wind speed and wind direction. 
wind_direction  Calculate meteorological wind direction from zonal and meridional wind components. 
z2geouv  Computes the geostrophic zonal and meridional wind components using geopotential height on isobaric levels (rectilinear grid only). 
zonal_mpsi  Computes a zonal mean meridional stream function. 
zonal_mpsi_Wrap  Computes a zonal mean meridional stream function and retains metadata. 
NCL object routines
attsetvalues  Applies resources to the given objects. 
create_graphic  Creates a graphic object 
destroy  Destroys objects from NCL. 
get_isolines  Retrieves the points that define a contour line. 
list_hlus  Lists all of the HLU objects currently referenced by NCL variables. 
NhlAddAnnotation  Add annotations to a plot object as an external annotation. 
NhlAddData  Adds one or more additional data items to a plot. 
NhlAddOverlay  Overlays one plot object on another. 
NhlAddPrimitive  Adds a Primitive object to an existing plot. 
NhlAppGetDefaultParentId  Returns a reference to the current default App object. 
NhlClassName  Retrieve the class name of one or more NCL objects. 
NhlDestroy  Destroys objects from NCL. 
NhlGetBB  Retrieves the bounding boxes of a list of NCL objects. 
NhlGetClassResources  Returns a list of resources associated with the given class name and an optional filter string. 
NhlGetErrorObjectId  Returns a reference to the current Error object. 
NhlGetParentId  Returns the ids of the parent ids of the given objects. 
NhlGetWorkspaceObjectId  Returns a reference to the current Workspace object. 
NhlIsApp  Returns True for each given object that is an App object. 
NhlIsDataComm  Returns True for each given object that is a DataComm object. 
NhlIsDataItem  Returns True for each given object that is a DataItem object. 
NhlIsDataSpec  Returns True for each given object that is a DataSpec object. 
NhlIsTransform  Returns True for each given object that is a Transform object. 
NhlIsView  Returns True for each given object that is a View object. 
NhlName  Retrieves the name of one or more NCL objects. 
NhlRemoveAnnotation  Remove annotations from the plot they are registered in. 
NhlRemoveData  Removes data items from one or more plots. 
NhlRemoveOverlay  Removes one or more plots from an overlay. 
NhlRemovePrimitive  Removes one or more primitives from the given Transform object. 
NhlUpdateData  Forces the DataComm instances to update their internal states. 
overlay  Overlays one plot object on another. 
Oceanography
depth_to_pres  Convert ocean depth to pressure. 
mixed_layer_depth  Calculates a quantity derived from the Potential Density of significance. (Documentation under construction.) 
pop_remap  Regrids a POP ocean model grid to another grid. 
PopLatLon  Regrids a scalar variable on a POP grid to a lat/lon grid or viceversa. 
PopLatLonV  Converts vectors on a POP grid to a lat/lon grid and viceversa. 
potmp_insitu_ocn  Calculate seawater potential temperature at an arbitrary reference pressure given insitu temperature, salinity and depth. 
rho_mwjf  Computes ocean water density given a specified range for potential temperature (deg Celisus) and salinity (psu). 
Printing
Prints the value of a variable or expression.  
printFileVarSummary  Prints a summary of a file variable's information. 
printMinMax  Prints the minimum and maximum values of a variable. 
printVarSummary  Prints a summary of a variable's information. 
show_ascii  Prints the ASCII table to the screen. 
write_matrix  Writes nicelyformatted integer, float, or double precision twodimensional (2D) arrays to standard out or to a file. 
Random number generators
generate_2d_array  Generates a "nice" 2D array of pseudo random data, especially for use in 2D graphics. 
generate_unique_indices  Generate unique random indices (subscripts). 
rand  Generates a pseudo random number. 
random_chi  Generates random numbers using a chisquared distribution. 
random_gamma  Generates random numbers using a gamma distribution. 
random_normal  Generates random numbers using a normal distribution. 
random_setallseed  Sets initial seeds for random number generators. 
random_uniform  Generates random numbers using a uniform range distribution. 
srand  Establishes a seed for the rand function. 
Regridding
area_conserve_remap  Performs areal conservative remapping from one rectilinear grid to another. 
area_conserve_remap_Wrap  Performs areal conservative remapping from one rectilinear grid to another and preserves meta data. 
area_hi2lores  Interpolates from high resolution rectilinear grids to low resolution recitlinear grids using local area averaging. 
area_hi2lores_Wrap  Interpolates from high resolution rectilinear grids to low resolution rectilinear grids using local area averaging. (retains meta data) 
bin_avg  Calculates gridded binned averages and counts using randomly spaced data. 
curvilinear_to_SCRIP  Writes the description of a curvilinear grid to a SCRIP file. 
ESMF_regrid  Regrids data from one lat/lon grid to another, using ESMF software. 
ESMF_regrid_gen_weights  Writes a weight file using the offline ESMF weight generator. 
ESMF_regrid_with_weights  Using the provided weight file, regrids data from one lat/lon grid to another. 
f2fosh  Interpolates a scalar quantity from a fixed grid (including pole points) to a fixedoffset grid. 
f2fosh_Wrap  Interpolates a scalar quantity from a fixed grid (including pole points) to a fixedoffset grid (retains metadata). 
f2foshv  Interpolates a vector quantity on a fixed grid (including pole points) to a fixedoffset grid. 
f2foshv_Wrap  Interpolates a vector quantity on a fixed grid (including pole points) to a fixedoffset grid (retains metadata). 
f2fsh  Interpolates a scalar quantity from one fixed grid to another. 
f2fsh_Wrap  Interpolates a scalar quantity from one fixed grid to another (retains metadata). 
f2fshv  Interpolates a vector quantity from one fixed grid to another. 
f2fshv_Wrap  Interpolates a vector quantity from one fixed grid to another (retains metadata). 
f2gsh  Interpolates a scalar quantity from a fixed grid to a Gaussian grid (with optional truncation). 
f2gsh_Wrap  Interpolates a scalar quantity from a fixed grid to a Gaussian grid (with optional truncation) (retains metadata). 
f2gshv  Interpolates a vector quantity on a fixed grid to a Gaussian grid (optional truncation). 
f2gshv_Wrap  Interpolates a vector quantity on a fixed grid to a Gaussian grid (optional truncation) (retains metadata). 
fo2fsh  Interpolates a scalar quantity from a fixedoffset grid to a fixed grid. 
fo2fsh_Wrap  Interpolates a scalar quantity from a fixedoffset grid to a fixed grid (retains metadata). 
fo2fshv  Interpolates a vector quantity from a fixedoffset grid to a fixed grid. 
fo2fshv_Wrap  Interpolates a vector quantity from a fixedoffset grid to a fixed grid (retains metadata). 
ftsurf  Calculates an interpolatory surface passing through a rectangular grid of function values. 
g2fsh  Interpolates a scalar quantity from a Gaussian grid to a fixed grid. 
g2fsh_Wrap  Interpolates a scalar quantity from a Gaussian grid to a fixed grid (retains metadata). 
g2fshv  Interpolates a vector quantity from a Gaussian grid to a fixed grid. 
g2fshv_Wrap  Interpolates a vector quantity from a Gaussian grid to a fixed grid (retains metadata). 
g2gsh  Interpolates a scalar quantity from one Gaussian grid to another (with optional truncation). 
g2gsh_Wrap  Interpolates a scalar quantity from one Gaussian grid to another (with optional truncation) (retains metadata). 
g2gshv  Interpolates a vector quantity from one Gaussian to another (optional truncation). 
g2gshv_Wrap  Interpolates a vector quantity from one Gaussian to another (optional truncation) (retains metadata). 
latlon_to_SCRIP  Writes the description of a lat/lon grid to a SCRIP file. 
linint2  Interpolates from a rectilinear grid to another rectilinear grid using bilinear interpolation. 
linint2_points  Interpolates from a rectilinear grid to an unstructured grid using bilinear interpolation. 
linint2_points_Wrap  Interpolates from a rectilinear grid to an unstructured grid using bilinear interpolation, and retains metadata. 
linint2_Wrap  Interpolates from a rectilinear grid to another rectilinear grid using bilinear interpolation, and retains metadata. 
obj_anal_ic  Iterative improvement objective analysis. 
obj_anal_ic_deprecated  Iterative correction objective analysis (Cressman, Barnes). 
obj_anal_ic_Wrap  Iterative improvement objective analysis and returns meta data. 
poisson_grid_fill  Replaces all missing (_FillValue) values in a grid with values derived from solving Poisson's equation via relaxation. 
pop_remap  Regrids a POP ocean model grid to another grid. 
PopLatLon  Regrids a scalar variable on a POP grid to a lat/lon grid or viceversa. 
PopLatLonV  Converts vectors on a POP grid to a lat/lon grid and viceversa. 
rcm2points  Interpolates data on a curvilinear grid (i.e. RCM, WRF, NARR) to an unstructured grid. 
rcm2points_Wrap  Interpolates data on a curvilinear grid (i.e. RCM, WRF, NARR) to an unstructured grid and retains metadata. 
rcm2rgrid  Interpolates data on a curvilinear grid (i.e. RCM, WRF, NARR) to a rectilinear grid. 
rcm2rgrid_Wrap  Interpolates data on a curvilinear grid (i.e. RCM, WRF, NARR) to a rectilinear grid and retains metadata. 
rectilinear_to_SCRIP  Writes the description of a rectilinear grid to a SCRIP file. 
rgrid2rcm  Interpolates data on a rectilinear lat/lon grid to a curvilinear grid like those used by the RCM, WRF and NARR models/datasets. 
rgrid2rcm_Wrap  Interpolates data on a rectilinear lat/lon grid to a curvilinear grid like those used by the RCM, WRF and NARR models/datasets and retains metadata. 
triple2grid  Places unstructured (randomlyspaced) data onto the nearest locations of a rectilinear grid. 
triple2grid2d  Places unstructured (randomlyspaced) data onto the nearest locations of a curvilinear grid. 
triple2grid_Wrap  Places unstructured (randomlyspaced) data onto the nearest locations of a rectilinear grid and retains metadata. 
unstructured_to_ESMF  Writes the description of an unstructured grid to an ESMF file. 
RIP
rip_cape_2d  Computes convective available potential energy (CAPE), convective inhibition (CIN), lifted condensation level (LCL), and level of free convection (LFC) (deprecated version). 
rip_cape_3d  Computes convective available potential energy (CAPE) and convective inhibition (CIN) (deprecated version). 
wrf_cape_2d  Computes maximum convective available potential energy (CAPE), maximum convective inhibition (CIN), lifted condensation level (LCL), and level of free convection (LFC). 
wrf_cape_3d  Computes convective available potential energy (CAPE) and convective inhibition (CIN). 
Singular value decomposition
dgeevx_lapack  Given a square (N,N) real nonsymmetric matrix, compute the eigenvalues and, optionally, the left and/or right eigenvectors via the LAPACK subroutine dgeevx. 
svd_lapack  Calculates the singular value decomposition of a general rectangular matrix. 
svdcov  Uses singular value decomposition and returns the left and right homogeneous and heterogeneous arrays associated with the two input datasets. 
svdcov_sv  Uses singular value decomposition to return the left and right singular vectors associated with the two input datasets. 
svdstd  Uses singular value decomposition and returns the left and right homogeneous and heterogeneous arrays associated with the two input datasets. 
svdstd_sv  Uses singular value decomposition to return the left and right singular vectors associated with the two input datasets. 
Spherical harmonic routines
dv2uvF  Computes the divergent (irrotational) wind components for a fixed grid via spherical harmonics. 
dv2uvf  Computes the divergent (irrotational) wind components for a fixed grid via spherical harmonics. 
dv2uvF_Wrap  Computes the divergent (irrotational) wind components for a fixed grid via spherical harmonics and retains metadata. 
dv2uvG  Computes the divergent (irrotational) wind components for a gaussian grid via spherical harmonics. 
dv2uvg  Computes the divergent (irrotational) wind components for a gaussian grid via spherical harmonics. 
dv2uvG_Wrap  Computes the divergent (irrotational) wind components for a gaussian grid via spherical harmonics and retains metadata. 
exp_tapersh  Performs tapering (filtering) of the spherical harmonic coefficients. 
exp_tapersh_wgts  Calculates weights which can be used to perform tapering (filtering) of spherical harmonic coefficients. 
exp_tapershC  Performs tapering (filtering) of the spherical harmonic coefficients. 
get_sphere_radius  Retrieves the radius of a sphere used in spherical harmonic routines. 
gradsf  Computes the gradient of an array that is on a fixed grid using spherical harmonics. 
gradsg  Computes the gradient of an array that is on a gaussian grid using spherical harmonics. 
igradsf  Computes a scalar array from its gradient components on a fixed grid using spherical harmonics. 
igradsF  Computes a scalar array from its gradient components on a fixed grid using spherical harmonics. 
igradsg  Computes a scalar array from its gradient components on a gaussian grid using spherical harmonics. 
igradsG  Computes a scalar array from its gradient components on a gaussian grid using spherical harmonics. 
ilapsf  Inverts the Laplacian (on a fixed grid) using spherical harmonics. 
ilapsF  Inverts the Laplacian (on a fixed grid) using spherical harmonics. 
ilapsF_Wrap  Inverts the Laplacian (on a fixed grid) using spherical harmonics and retains metadata. 
ilapsg  Inverts the Laplacian (on a gaussian grid) using spherical harmonics. 
ilapsG  Inverts the Laplacian (on a gaussian grid) using spherical harmonics. 
ilapsG_Wrap  Inverts the Laplacian (on a gaussian grid) using spherical harmonics and retains metadata. 
ilapvf  Inverts the vector Laplacian (on a fixed grid) using spherical harmonics. 
ilapvg  Inverts the vector Laplacian (on a gaussian grid) using spherical harmonics. 
lapsF  Computes the Laplacian using spherical harmonics, given a scalar z on a fixed grid. 
lapsf  Computes the Laplacian using spherical harmonics, given a scalar z on a fixed grid. 
lapsG  Computes the Laplacian using spherical harmonics, given a scalar z on a gaussian grid. 
lapsg  Computes the Laplacian using spherical harmonics, given a scalar z on a gaussian grid. 
lapvf  Computes the vector Laplacian using spherical harmonics, given a vector quantity (u,v) on a fixed grid. 
lapvg  Computes the vector Laplacian using spherical harmonics, given a vector quantity (u,v) on a gaussian grid. 
lderuvf  Computes the latitudinal derivatives using spherical harmonics, given vector components (u,v) on a fixed grid. 
lderuvg  Computes the latitudinal derivatives using spherical harmonics, given vector components (u,v) on a gaussian grid. 
rhomb_trunc  Performs rhomboidal truncation on spherical harmonic coefficients. 
rhomb_trunC  Performs rhomboidal truncation on spherical harmonic coefficients. 
set_sphere_radius  Sets the radius of a sphere used in spherical harmonic routines. 
sfvp2uvf  Computes the wind components given stream function and velocity potential (on a fixed grid) via spherical harmonics. 
sfvp2uvg  Computes the wind components given stream function and velocity potential (on a gaussian grid) via spherical harmonics. 
shaeC  Computes spherical harmonic analysis of a scalar field on a fixed grid via spherical harmonics. 
shaec  Computes spherical harmonic analysis of a scalar field on a fixed grid via spherical harmonics. 
shagC  Computes spherical harmonic analysis of a scalar field on a gaussian grid via spherical harmonics. 
shagc  Computes spherical harmonic analysis of a scalar field on a gaussian grid via spherical harmonics. 
shsec  Computes spherical harmonic synthesis of a scalar quantity on a fixed grid via spherical harmonics. 
shseC  Computes the spherical harmonic synthesis of a scalar quantity on a fixed grid via spherical harmonics. 
shsgc  Computes spherical harmonic synthesis of a scalar quantity on a gaussian grid via spherical harmonics. 
shsgC  Computes the spherical harmonic synthesis of a scalar quantity on a gaussian grid via spherical harmonics. 
shsgc_R42  Computes spherical harmonic synthesis of a scalar quantity via rhomboidally truncated (R42) spherical harmonic coefficients onto a (108x128) gaussian grid. 
shsgc_R42_Wrap  Computes spherical harmonic synthesis of a scalar quantity via rhomboidally truncated (R42) spherical harmonic coefficients onto a (108x128) gaussian grid. (creates metadata). 
tri_trunC  Performs triangular truncation on spherical harmonic coefficients. 
tri_trunc  Performs triangular truncation on spherical harmonic coefficients. 
uv2dvf  Computes the divergence using spherical harmonics given the u and v wind components on a fixed grid. 
uv2dvF  Computes the divergence using spherical harmonics given the u and v wind components on a fixed grid. 
uv2dvF_Wrap  Computes the divergence using spherical harmonics given the u and v wind components on a fixed grid (retains metadata). 
uv2dvg  Computes the divergence using spherical harmonics given the u and v wind components on a gaussian grid. 
uv2dvG  Computes the divergence using spherical harmonics given the u and v wind components on a gaussian grid. 
uv2dvG_Wrap  Computes the divergence using spherical harmonics given the u and v wind components on a gaussian grid (retains metadata). 
uv2sfvpF  Computes the stream function and velocity potential via spherical harmonics given u and v on a fixed grid. 
uv2sfvpf  Computes the stream function and velocity potential via spherical harmonics given u and v on a fixed grid. 
uv2sfvpG  Computes the stream function and velocity potential via spherical harmonics given u and v on a gaussian grid. 
uv2sfvpg  Computes the stream function and velocity potential via spherical harmonics given u and v on a gaussian grid. 
uv2vrdvF  Computes the vorticity and divergence via spherical harmonics, given the u and v wind components on a fixed grid. 
uv2vrdvf  Computes the vorticity and divergence via spherical harmonics, given the u and v wind components on a fixed grid. 
uv2vrdvg  Computes the vorticity and divergence via spherical harmonics, given the u and v wind components on a gaussian grid. 
uv2vrdvG  Computes the vorticity and divergence via spherical harmonics, given the u and v wind components on a gaussian grid. 
uv2vrF  Computes the vorticity via spherical harmonics, given the u and v wind components on a fixed grid. 
uv2vrf  Computes the vorticity via spherical harmonics, given the u and v wind components on a fixed grid. 
uv2vrF_Wrap  Computes the vorticity via spherical harmonics, given the u and v wind components on a fixed grid (retains metadata). 
uv2vrG  Computes the vorticity via spherical harmonics, given the u and v wind components on a gaussian grid. 
uv2vrg  Computes the vorticity via spherical harmonics, given the u and v wind components on a gaussian grid. 
uv2vrG_Wrap  Computes the vorticity via spherical harmonics, given the u and v wind components on a gaussian grid (retains metadata). 
vhaeC  Computes vector spherical harmonic analysis of vector fields on a fixed grid via spherical harmonics. 
vhaec  Computes vector spherical harmonic analysis of vector fields on a fixed grid via spherical harmonics. 
vhagC  Computes vector spherical harmonic analysis of vector fields on a gaussian grid via spherical harmonics. 
vhagc  Computes vector spherical harmonic analysis of vector fields on a gaussian grid via spherical harmonics. 
vhseC  Computes vector spherical harmonic syntheses of vector fields on a fixed grid via spherical harmonics. 
vhsec  Computes vector spherical harmonic syntheses of vector fields on a fixed grid via spherical harmonics. 
vhsgc  Computes vector spherical harmonic syntheses of vector fields on a gaussian grid via spherical harmonics. 
vhsgC  Computes vector spherical harmonic syntheses of vector fields on a gaussian grid via spherical harmonics. 
vr2uvf  Computes the rotational wind components via spherical harmonics, given an array containing relative vorticity on a fixed grid. 
vr2uvF  Computes the rotational wind components via spherical harmonics, given an array containing relative vorticity on a fixed grid. 
vr2uvF_Wrap  Computes the rotational wind components via spherical harmonics, given an array containing relative vorticity on a fixed grid (retains metadata). 
vr2uvg  Computes the rotational wind components via spherical harmonics, given an array containing relative vorticity on a gaussian grid. 
vr2uvG  Computes the rotational wind components via spherical harmonics, given an array containing relative vorticity on a gaussian grid. 
vr2uvG_Wrap  Computes the rotational wind components via spherical harmonics, given an array containing relative vorticity on a gaussian grid (retains metadata). 
vrdv2uvf  Computes the wind components via spherical harmonics, given vorticity and divergence on a fixed grid. 
vrdv2uvF  Computes the wind components via spherical harmonics, given vorticity and divergence on a fixed grid. 
vrdv2uvg  Computes the wind components via spherical harmonics, given vorticity and divergence on a gaussian grid. 
vrdv2uvG  Computes the wind components via spherical harmonics, given vorticity and divergence on a gaussian grid. 
String manipulators
changeCase  Changes the case of a string. (Deprecated: see str_lower/str_upper.) 
changeCaseChar  Changes the case of each character in a string. (Deprecated: see str_switch.) 
charactertostring  Coerces values of type character to values of type string. 
chartostring  Coerces values of type character to values of type string. 
get_file_suffix  Extract the suffix associated with a file name. 
indStrSubset  Returns the indices corresponding to the location of the substring, if it is a subset of the other given string. (Deprecated: see str_index_of_substr.) 
isStrSubset  Return True or False if one string is a subset of another string. 
oneDtostring  Converts a 1dimensional array to a single string. 
print_table  Prints all elements from a list (to stdout). 
replaceSingleChar  Within a string replace one character with another character. (Deprecated: see str_sub_str.) 
sprintf  Converts floats or doubles into formatted strings. 
sprinti  Converts integers into formatted strings. 
str_capital  Capitalizes all words in each string. 
str_concat  Concatenates all strings into a single string. 
str_fields_count  Counts the number of fields separated by the given delimiters in an array of strings. 
str_get_cols  Returns an array of substrings, given a start and end index into the given string. 
str_get_dq  Returns the double quote (") character as a string. 
str_get_field  Returns an array of substrings given a field number and a combination of delimiters. 
str_get_nl  Returns the newline (\n) character as a string. 
str_get_sq  Returns the single quote (') character as a string. 
str_get_tab  Returns the tab ('\t' in C) character as a string. 
str_index_of_substr  Returns the start indexes where one or more occurrences of a substring is found in a string. 
str_insert  Inserts a substring into the given strings. 
str_is_blank  Returns True for strings that contain all blanks. 
str_join  Joins all strings into one string, with each string separated by delimiter. 
str_left_strip  Strips leading spaces and TABs from the input strings. 
str_lower  Converts all input strings to lowercase. 
str_match  Returns a list of strings that contain the given substring (case sensitive). 
str_match_ic  Returns a list of strings that contain the given substring (case insensitive). 
str_match_ind  Returns a list of indexes into an array of strings that contain the given substring (case sensitive). 
str_match_ind_ic  Returns a list of indexes into an array of strings that contain the given substring (case insensitive). 
str_right_strip  Strips ending spaces and TABs from the input strings. 
str_split  Splits a string into an array of strings given a delimiter. 
str_split_by_length  Splits a string or strings into an array of strings given a length, or an array of lengths. 
str_split_csv  Splits strings into an array of strings using the given delimiter. 
str_squeeze  Strips off leading and ending spaces and TABs, and replaces multiple spaces and/or TABs with a single space. 
str_strip  Strips leading and ending spaces and TABs from the input strings. 
str_sub_str  Replaces a substring with a new substring. 
str_switch  Switches the case of characters in the given string(s). 
str_upper  Converts all input strings to uppercase. 
stringtochar  Coerces values of type string to values of type character. 
stringtocharacter  Coerces values of type string to values of type character. 
stringtodouble  Coerces values of type string to values of type double. 
stringtofloat  Coerces values of type string to values of type float. 
stringtoint  Coerces values of type string to values of type integer. 
stringtointeger  Coerces values of type string to values of type integer. 
stringtolong  Coerces values of type string to values of type long. 
stringtoshort  Coerces values of type string to values of type short. 
strlen  Returns the length of a string variable. 
unique_string  Returns a unique string given the input string as a prefix. 
write_table  Writes all elements from a list (to a file). 
System tools
echo_off  Disables echoing of NCL statements as they are encountered. 
echo_on  Enables echoing of NCL statements as they are encountered. 
exit  Forces an NCL script to exit immediately. 
fileexists  Checks for existence of any UNIX file. 
get_cpu_time  Returns the CPU time used by NCL. 
get_ncl_version  Returns the current NCL version. 
get_script_name  Returns the name of a script of commands provided to NCL for execution. 
get_script_prefix_name  Returns the name of a script of commands provided to NCL for execution, if provided, with any script name tag removed. 
getenv  Returns the string value of a shell environment variable. 
isbigendian  Returns True if you are running NCL on a big endian machine. 
isfilepresent  Checks if a supported file exists. 
loadscript  Loads the given NCL script. 
ncargpath  Returns the absolute pathnames of various NCAR Graphics directories. 
ncargversion  Prints the NCAR Graphics version, copyright, trademark and general licensing terms. 
print_clock  Prints the given string along with a current timestamp. 
sleep  Pauses execution of NCL scripts for a specified number of seconds. 
status_exit  Exits an NCL script passing a status code to the calling environment. 
system  Executes a shell command. 
systemfunc  Executes a shell command and returns the output. 
unique_string  Returns a unique string given the input string as a prefix. 
wallClockElapseTime  Calculates and prints elapsed 'wall clock' time. 
Type converters
byte2flt  Converts values of type byte to values of type float. 
byte2flt_hdf  Converts values of type byte to values of type float using the "scale" and "offset" attributes (if present). 
charactertodouble  Coerces values of type character to values of type double. 
charactertofloat  Coerces values of type character to values of type float. 
charactertointeger  Coerces values of type character to values of type integer. 
charactertolong  Coerces values of type character to values of NCL type long. 
charactertoshort  Coerces values of type character to values of type short. 
charactertostring  Coerces values of type character to values of type string. 
chartodouble  Coerces values of type character to values of type double. 
chartofloat  Coerces values of type character to values of type float. 
chartoint  Coerces values of type character to values of type integer. 
chartointeger  Coerces values of type character to values of type integer. 
chartolong  Coerces values of type character to values of NCL type long. 
chartoshort  Coerces values of type character to values of type short. 
chartostring  Coerces values of type character to values of type string. 
cshstringtolist  Converts a comma delimited string from csh and breaks it up into separate strings. 
datatondc  Converts data units into normalized device coordinates (NDCs). 
dble2flt  Converts values of type double to values of type float and preserves metadata. 
doubletobyte  Coerces values of type double to values of type byte. 
doubletochar  Coerces values of type double to values of type character. 
doubletocharacter  Coerces values of type double to values of type character. 
doubletofloat  Coerces values of type double to values of type float. 
doubletoint  Coerces values of type double to values of type integer. 
doubletointeger  Coerces values of type double to values of type integer. 
doubletolong  Coerces values of type double to values of type long. 
doubletoshort  Coerces values of type double to values of type short. 
floattobyte  Coerces values of type float to values of type byte. 
floattochar  Coerces values of type float to values of type character. 
floattocharacter  Coerces values of type float to values of type character. 
floattoint  Coerces values of type float to values of type integer. 
floattointeger  Coerces values of type float to values of type integer. 
floattolong  Coerces values of type float to values of type long. 
floattoshort  Coerces values of type float to values of type short. 
flt2dble  Converts values of type float to values of type double and preserves metadata. 
flt2string  Converts values of type float to values of type string. 
int2dble  Converts values of type integer to values of type float and preserves metadata. 
int2flt  Converts values of type integer to values of type float and preserves metadata. 
integertobyte  Coerces values of type integer to values of type byte. 
integertochar  Coerces values of type integer to values of type character. 
integertocharacter  Coerces values of type integer to values of type character. 
integertoshort  Coerces values of type integer to values of type short. 
inttobyte  Coerces values of type integer to values of type byte. 
inttochar  Coerces values of type integer to values of type character. 
inttoshort  Coerces values of type integer to values of type short. 
longtobyte  Coerces values of type long to values of type byte. 
longtochar  Coerces values of type long to values of type character. 
longtocharacter  Coerces values of type long to values of type character. 
longtoint  Coerces values of type long to values of type integer. 
longtointeger  Coerces values of type long to values of type integer. 
longtoshort  Coerces values of type long to values of type short. 
ndctodata  Converts normalized device coordinates (NDCs) into data coordinates. 
NhlDataToNDC  Converts data units into normalized device coordinates (NDCs). 
NhlNDCToData  Converts normalized device coordinates (NDCs) into data coordinates. 
numeric2int  Converts values of any numeric type to type integer. 
pack_values  Compress values of type float or double to values of type short or byte. 
short2flt  Converts values of type short to values of type float using the "scale" and "offset" attributes (if present). 
short2flt_hdf  Converts values of type short to values of type float using the "scale" and "offset" attributes (if present). 
shorttobyte  Coerces values of type short to values of type byte. 
shorttochar  Coerces values of type short to values of type character. 
shorttocharacter  Coerces values of type short to values of type character. 
stringtochar  Coerces values of type string to values of type character. 
stringtocharacter  Coerces values of type string to values of type character. 
stringtodouble  Coerces values of type string to values of type double. 
stringtofloat  Coerces values of type string to values of type float. 
stringtoint  Coerces values of type string to values of type integer. 
stringtointeger  Coerces values of type string to values of type integer. 
stringtolong  Coerces values of type string to values of type long. 
stringtoshort  Coerces values of type string to values of type short. 
time_to_newtime  Change a "udunits" recognized time unit to a new (different) "udunits" recognized time unit. 
tobyte  Converts values of any snumeric data type or string to values of type (NCL) byte (unsigned char). 
tochar  Converts values of any snumeric data type or string to values of type char. 
todouble  Converts values of any snumeric data type or string to values of type double. 
tofloat  Converts values of any snumeric data type or string to values of type float. 
toint  Converts values of any snumeric data type or string to values of type integer. 
toint64  Converts values of any snumeric data type or string to values of type int64 (64 bit long, or long long). 
tointeger  Converts values of any snumeric data type or string to values of type integer. 
tolong  Converts values of any snumeric data type or string to values of type long. 
toshort  Converts values of any snumeric data type or string to values of type short. 
tosigned  Converts any kind of 8/16/32/64 integers to its coresponding signed integers. 
tostring  Converts values of any snumeric data type to values of type string. 
tostring_with_format  Converts values of any snumeric data type to values of type string, with specified format. 
totype  Converts values of any snumeric data type or string to values of the given type. 
toubyte  Converts values of any snumeric data type or string to values of type unsigned byte. 
touint  Converts values of any snumeric data type or string to values of type unsigned integer. 
touint64  Converts values of any snumeric data type or string to values of type uint64 (unsigned 64 bit long, or unsigned long long). 
toulong  Converts values of any snumeric data type or string to values of type unsigned long. 
tounsigned  Converts any kind of 8/16/32/64 integers to its coresponding unsigned integers. 
toushort  Converts values of any snumeric data type or string to values of type unsigned short. 
ushorttoint  Coerces values of type unsigned short to values of type integer. 
Unclassified routines
dim_spei_n  Calculate the standardized precipitation evapotransporation index (SPEI). 
dim_spi_n  Calculate the standardized precipitation index (SPI). 
dim_thornthwaite_n  Estimate the potential evapotranspiration (PET) via the Thornthwaite method. 
rtest  Determines the statistical significance of a linear correlation coefficient. 
Variable manipulators
array_append_record  Attaches [appends] additional records [leftmost dimension] to a previously existing array. 
delete  Deletes variables, attributes, and coordinate variables. 
merge_levels_sfc  Merges a multiple level variable with the corresponding surface variable. 
new  Creates an NCL variable. 
replace_ieeenan  Changes all occurrences of IEEE NaN to a userspecified value. 
rm_single_dims  Removes (squeezes) singleton (degenerate) dimensions from an array while preserving meta data. 
table_attach_columns  Attaches [appends] additional columns to a previously existing twodimensional array. 
table_attach_rows  Attaches [appends] additional rows to a previously existing twodimensional array. 
undef  Undefines defined NCL symbols (functions, procedures, variables). 
Variable query
isbyte  Returns True if input is of type byte. 
ischar  Returns True if input is of type char. 
isdefined  Returns True for every element of the input that is a defined keyword, variable, or function/procedure name. 
isdouble  Returns True if input is of type double. 
isenumeric  Returns True if input is of type enumeric. 
isfloat  Returns True if input is of type float. 
isfunc  Returns True for every element of the input that is a defined function. 
isgraphic  Returns True if input is of type graphic. 
isint  Returns True if input is of type integer. 
isint64  Returns True if input is of type int64. 
isinteger  Returns True if input is of type integer. 
islogical  Returns True if input is of type logical. 
islong  Returns True if input is of type long. 
isnan_ieee  Returns a logical array indicating which input values contain an IEEE NaN. 
isnumeric  Returns True if input is of type numeric. 
isproc  Returns True for every element of the input that is a defined procedure. 
isshort  Returns True if input is of type short. 
issnumeric  Returns True if input is of type snumeric. 
isstring  Returns True if input is of type string. 
isubyte  Returns True if input is of type ubyte. 
isuint  Returns True if input is of type uint. 
isuint64  Returns True if input is of type uint64. 
isulong  Returns True if input is of type ulong. 
isunsigned  Returns True if input is one of the unsigned types. 
isushort  Returns True if input is of type short. 
isvar  Returns True for every element of the input that is a defined variable. 
list_procfuncs  Lists all of the currently defined NCL functions and procedures and their argument lists. 
list_vars  Lists the currently defined variables that do not reference files or HLU objects. 
sizeof  Returns the total size, in bytes, of the input variable. 
typeof  Returns the string name of the type of the input variable. 
Workstation routines
clear  Clears the given workstation objects. 
frame  Updates and clears the given workstation objects. 
NhlChangeWorkstation  Changes the output workstation of one or more NCL View objects. 
NhlClearWorkstation  Clears the given workstation objects. 
NhlFrame  Updates and clears the given workstation objects. 
NhlGetParentWorkstation  Returns the ids of the parent workstations of the given objects. 
NhlIsWorkstation  Returns True for each given object that is a Workstation object. 
NhlUpdateWorkstation  Updates the given workstation objects. 
update  Updates the given workstation objects. 
WRF
wrf_avo  Calculates absolute vorticity from WRF model output. 
wrf_cape_2d  Computes maximum convective available potential energy (CAPE), maximum convective inhibition (CIN), lifted condensation level (LCL), and level of free convection (LFC). 
wrf_cape_3d  Computes convective available potential energy (CAPE) and convective inhibition (CIN). 
wrf_contour  Creates a contour plot from ARW WRF model output. 
wrf_dbz  Calculates simulated equivalent radar reflectivity factor [dBZ] from WRF model output. 
wrf_eth  Calculates equivalent potential temperature from WRF model output. 
wrf_helicity  Calculates storm relative helicity from WRF model output. 
wrf_ij_to_ll  Finds the nearest longitude, latitude locations to the specified model grid indices (i,j). 
wrf_interp_1d  Linearly interpolates a onedimensional variable in the vertical. 
wrf_interp_2d_xy  Extracts a cross section from a given input field. 
wrf_interp_3d_z  Interpolates to a specified pressure/height level. 
wrf_latlon_to_ij  Finds the nearest model grid indices (i,j) to the specific location(s) in latitude and longitude (deprecated). 
wrf_ll_to_ij  Finds the nearest model grid indices (i,j) to the specified location(s) in longitude and latitude. 
wrf_map  Creates a map background for ARW WRF model data. 
wrf_map_overlay  Overlays different plot id's over a map background (deprecated in version 5.1.0). 
wrf_map_overlays  Overlays different contour and vector plots over a WRFARW map background. 
wrf_map_resources  Sets map plotting resources based on an input WRFARW file. 
wrf_map_zoom  Zooms into a portion of the ARW WRF model domain, and creates a map background (deprecated in version 5.1.0). 
wrf_mapres_c  Sets the appropriate geographical mapping resources based upon WRF file contents. (deprecated) 
wrf_omega  Calculates approximate omega in C, given vertical velocity, water vapor mixing ratio, temperature, and pressure from WRF model output. 
wrf_overlay  Overlays multiple plots, created from other ARW WRF plot functions (deprecated in version 5.1.0). 
wrf_overlays  Overlays multiple plots, created from other ARW WRF plot functions. 
wrf_pvo  Calculates potential vorticity from WRF model output. 
wrf_rh  Calculates relative humidity from ARW WRF model output. 
wrf_slp  Calculates sea level pressure from ARW WRF model output. 
wrf_smooth_2d  Smooths a given field. 
wrf_td  Calculates dewpoint temperature in [C] from ARW WRF model output. 
wrf_times_c  Converts WRF variable "Times" which is of type character to user specified numeric units. 
wrf_tk  Calculates temperature in [K] from ARW WRF model output. 
wrf_updraft_helicity  Calculates updraft helicity from WRF model output. 
wrf_user_getvar  Extracts data from ARW WRF model output, and does basic diagnostics calculations. 
wrf_user_ij_to_ll  Finds the nearest longitude, latitude locations to the specified model grid indices (i,j). 
wrf_user_intrp2d  Interpolates ARW WRF 2D model data along a give line. 
wrf_user_intrp3d  Interpolates ARW WRF model data vertically or horizontally. 
wrf_user_latlon_to_ij  Finds the nearest model grid indices (i,j) to the specific location (deprecated). 
wrf_user_list_times  Extracts the list of available times in the ARW WRF model output. 
wrf_user_ll_to_ij  Finds the nearest model grid indices (i,j) to the specified location(s) in longitude and latitude. 
wrf_user_unstagger  Unstaggers an input variable along a specified dimension. 
wrf_uvmet  Rotates u,v components of the wind to earth coordinates. 
wrf_vector  Creates a vector plot from ARW WRF model output. 
wrf_virtual_temp  Calculates virtual temperature, given temperature and mixing ratio from WRF model output. 
wrf_wetbulb  Calculates wet bulb temperature in C, given pressure in temperature in K and mixing ratio in kg/kg from WRF model output. 