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getfilevarnames

Returns an array of file variable names in the specified supported file.

Prototype

	function getfilevarnames (
		the_file [1] : file   
	)

	return_val [*] :  string

Arguments

the_file

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

Return value

This function returns an array of strings with each element containing the name of a variable. The length of this array is equal to the number of variables in the file.

Description

This function is useful when accessing file variables by string name. (See Files.)

Examples

The following example gets all the variables names from a netCDF file but it will also work for any file referenced by addfile. The dollar sign syntax used in this example is described at "NCL Variables". 

    f = addfile ("X.nc" , "r")   ; could also have ccm, grb or hdf suffux
    vNames = getfilevarnames (f) ; get names of all variables on file
      
    nNames = dimsizes (vNames)   ; number of variables on the file
      
    print (vNames)               ; print all variable names on file
      
    do n=0,nNames-1              ; loop thru each variable
       v = f->$vNames(n)$        ; read the varible to memory
         
       dimv = dimsizes(v)        ; dimension size of the variable
       rank = dimsizes(dimv)     ; rank [ie: number of dimensions]
         
       [SNIP]
         
       delete (v)
       delete (rank)
   end do