Scientific Data Formats: Network Common Data Format

NCDF_VARGET1

The NCDF_VARGET1 procedure retrieves one element from a netCDF variable. The netCDF file must be in data mode to use this procedure.

Syntax

NCDF_VARGET1, Cdfid, Varid, Value [, OFFSET=vector]

Arguments

Cdfid

The netCDF ID, returned from a previous call to NCDF_OPEN or NCDF_CREATE.

Varid

The netCDF variable ID, returned from a previous call to NCDF_VARDEF or NCDF_VARID, or the name of the variable.

Value

A named variable in which the value of the variable is returned. NCDF_VARGET1 sets Value's size and data type as appropriate.

Keywords

OFFSET

A vector containing the starting position of the read. The default starting position is [0, 0, ...].

Examples

Suppose that the file dave.nc contains an image saved with the netCDF variable name "dave". The following commands extract the value of a single pixel from the image:

; The location of the single element (pixel) whose value we will  
; retrieve:  
offset = [180,190]  
; Open the netCDF file:  
id = NCDF_OPEN('dave.nc')  
; Get the variable ID for variable "dave":  
varid = NCDF_VARID(id, 'dave')  
; Extract the element and return the value in the variable  
; single_pixel:  
NCDF_VARGET1, id, varid, single_pixel, OFFSET=offset  
; Close the netCDF file:  
NCDF_CLOSE, id