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lonGlobeFo

Generates longitudes and associated metadata for a global fixed offset grid.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"

	function lonGlobeFo (
		nlon     [1] : integer,  
		name     [1] : string,   
		longname [1] : string,   
		units    [1] : string    
	)

	return_val [*] :  float

Arguments

nlon

A scalar integer equal to the number of longitudes desired.

name

A string that will become the named dimension of the output (e.g. "lon").

longname

A string that will become the long_name of the output (e.g. "longitude").

units

A string that will become the units of the output (e.g. "degrees_north").

Return value

A one-dimensional array of size nlon. Default type float.

Description

Generates longitudes and associated metadata for a global fixed offset grid.

Examples

The following require that contributed.ncl be loaded prior to invoking the function.

       load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"

Create a one dimensional array of longitudes (coordinate array) offset from the Grenwich Meridion.

      mlon = 144
      lon  = lonGlobeFo(mlon, "lon", "longitude", "degrees_east")
      print(lon)

The above returns a 1D array of length mlon values.

Variable: lon
Type: float
Total Size: 576 bytes
            144 values
Number of Dimensions: 1
Dimensions and sizes:   [lon | 144]
Coordinates: 
            lon: [1.25..358.75]
Number Of Attributes: 2
  long_name :   longitude
  units :       degrees_east
(0)       1.25
(1)       3.75
(2)       6.25
(3)       8.75
(4)      11.25
[snip]
(139)   348.75
(140)   351.25
(141)   353.75
(142)   356.25
(143)   358.75

Note 1: if starting at the Internalional Dateline is desired,

      lon = (/ lon - 180. /)  ; subtract 180 from all values 
      lon&lon = lon           ; update coordinates
      print(lon)

The result:

Variable: lon
Type: float
Total Size: 576 bytes
            144 values
Number of Dimensions: 1
Dimensions and sizes:   [lon | 144]
Coordinates: 
Variable: lon
Type: float
Total Size: 576 bytes
            144 values
Number of Dimensions: 1
Dimensions and sizes:   [lon | 144]
Coordinates: 
            lon: [-178.75..178.75]
Number Of Attributes: 2
  long_name :   longitude
  units :       degrees_east
(0)     -178.75
(1)     -176.25
(2)     -173.75
(3)     -171.25
(4)     -168.75
[snip]
(139)    168.75
(140)    171.25
(141)    173.75
(142)    176.25
(143)    178.75

Note 2: If double precision is desired, set