comunpack.c File Reference

Unpack a data field that was packed using a complex packing algorithm as defined in the GRIB2 documention. More...

#include <stdio.h>
#include <stdlib.h>
#include "grib2_int.h"

Go to the source code of this file.

Functions
int	comunpack (unsigned char *cpack, g2int lensec, g2int idrsnum, g2int *idrstmpl, g2int ndpts, float *fld)
	This subroutine unpacks a data field that was packed using a complex packing algorithm as defined in the GRIB2 documention, using info from the GRIB2 Data Representation Template 5.2 or Template 5.3. More...

Detailed Description

Unpack a data field that was packed using a complex packing algorithm as defined in the GRIB2 documention.

Author

Stephen Gilbert

Date

2002-10-29

Definition in file comunpack.c.

Function Documentation

comunpack()

int comunpack	(	unsigned char *	cpack,
		g2int	lensec,
		g2int	idrsnum,
		g2int *	idrstmpl,
		g2int	ndpts,
		float *	fld
	)

This subroutine unpacks a data field that was packed using a complex packing algorithm as defined in the GRIB2 documention, using info from the GRIB2 Data Representation Template 5.2 or Template 5.3.

Supports GRIB2 complex packing templates with or without spatial differences (i.e. DRTs 5.2 and 5.3).

Program History Log

Date	Programmer	Comments
2002-10-29	Gilbert	Initial
2004-12-16	Gilbert	Added test (from Arthur Taylor/MDL) verifying group widths/lengths

Parameters

cpack	pointer to the packed data field.
lensec	length of section 7 (used for error checking).
idrsnum	Data Representation Template number. Must equal 2 or 3.
idrstmpl	pointer to the array of values for Data Representation Template 5.2 or 5.3
ndpts	The number of data values to unpack
fld	Contains the unpacked data values. Must be allocated with at least ndpts * sizeof(float) bytes before calling this routine.

Returns

0 for success, error code otherwise.

Author

Stephen Gilbert

Date

2002-10-29

Definition at line 42 of file comunpack.c.

References gbit(), gbits(), int_power(), and rdieee().

Referenced by g2_unpack7().