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getfilevarchunkdimsizes

Returns the chunk dimension sizes of variable on a file (which has chunk dimensions).

Prototype

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

	return_val [*] :  long

Arguments

thefile

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

varname

The string name of the variable whose chunk dimension sizes are desired.

Return value

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

Description

The getfilevarchunkdimsizes function should be used exclusively when querying the dimensionality of variables in files.

See Also

dimsizes, filevardimsizes, isfilevardim

Examples

Example 1 Consider a netCDF file where "ncl_filedump nc4uvt.nc" yields: 

Variable: f
Type: file
filename:       nc4uvt
path:   nc4uvt.nc
Number of Attributes:3
    Conventions :       None
    source_file :       nc4uvt.nc
    title       :       NCL generated netCDF file

dimensions:
    time        = 1 // unlimited
    lev = 14
    lat = 64
    lon = 128

chunk dimensions:
    time        = 1 // unlimited
    lev = 7
    lat = 32
    lon = 64

variables:
......

  a    = addfile("$NCARG_ROOT/lib/ncarg/data/cdf/nc4uvt.nc","r")
  dimt = getfilevarchunkdimsizes(a,"t")  
  print(dimt)
This produces the following output: 
Variable: dimt
Type: long
Total Size: 32 bytes
            4 values
Number of Dimensions: 1
Dimensions and sizes:   [4]
Coordinates: 
(0)     1
(1)     7
(2)     32
(3)     64