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getfilevardimsizes

Returns the dimension sizes of variable on a supported file.

Prototype

	function getfilevardimsizes (
		thefile [1] : file,    
		varname [1] : string   
	)

	return_val [*] :  integer

Arguments

thefile

reference to a file. It is created using addfile or addfiles. Thus, it must be a supported file format.

varname

string name of variable whose dimension sizes are desired

Return value

Returns a one dimensional array of dimension sizes for a file variable.

Description

This function works just like dimsizes, but for file variables. This function should be used rather than dimsizes when the variable is in a file. The dimsizes function is very inefficient to use on file variables because it reads in the entire variable. The getfilevardimsizes function should be used exclusively when querying the dimensionality of variables in files.

Note: This function is exactly the same as filevardimsizes. It was created for consistency purposes.

See Also

dimsizes, filevardimsizes, isfilevardim

Examples

Example 1 Consider a netCDF file where "ncdump -h Tstorm.nc" yields:

netcdf Tstorm {
dimensions:
        timestep = 64 ;
        lat = 33 ;
        lon = 36 ;
        timelen = 20 ;
variables:
        float t(timestep, lat, lon) ;
                t:_FillValue = -9999.f ;
        int timestep(timestep) ;
        float lat(lat) ;
        float lon(lon) ;
        char reftime(timelen) ;
                reftime:units = "text_time" ;
                reftime:long_name = "reference time" ;
}

  a    = addfile("$NCARG_ROOT/lib/ncarg/data/cdf/Tstorm.cdf","r")

  dimt = getfilevardimsizes(a,"t")  
  print(dimt)

This produces the following output:

Variable: dimt
Type: integer
Total Size: 12 bytes
            3 values
Number of Dimensions: 1
Dimensions and sizes:   [3]
Coordinates: 

(0)     64
(1)     33
(2)     36