Unpack Section 7 (Data Section) of a GRIB2 message. More...

#include "grib2_int.h"
#include <memory.h>
#include <string.h>

Functions
g2int	g2_unpack7 (unsigned char cgrib, g2int iofst, g2int igdsnum, g2int igdstmpl, g2int idrsnum, g2int idrstmpl, g2int ndpts, float **fld)
	This subroutine unpacks Section 7 (Data Section) of a GRIB2 message.

int	g2c_unpack7 (unsigned char cgrib, int igdsnum, int gds_tmpl_len, long long int gdstmpl, int idrsnum, int drs_tmpl_len, long long int drstmpl, int ndpts, float fld)
	This subroutine unpacks Section 7 (Data Section) of a GRIB2 message.

static g2int	g2c_unpack7_int (unsigned char cgrib, g2int iofst, g2int igdsnum, g2int igdstmpl, g2int idrsnum, g2int idrstmpl, g2int ndpts, int v1, float **fld)
	Unpacks Section 7 (Data Section) of a GRIB2 message.

Detailed Description

Unpack Section 7 (Data Section) of a GRIB2 message.

Author: Stephen Gilbert

Date: 2002-10-31

Program History Log

Date	Programmer	Comments
2002-10-31	Gilbert	Initial
2002-12-20	Gilbert	Added GDT info to arguments and added 5.51 processing.
2003-08-29	Gilbert	New templates using PNG and JPEG2000 algorithms/templates.
2004-11-29	Gilbert	JPEG2000 now allowed to use WMO Template 5.40 PNG allowed to use 5.41
2004-12-16	Taylor	Added check on comunpack return code.
2008-12-23	Wesley	Initialize Number of data points unpacked.
2022-10-04	Hartnett	Added g2c_unpack7().
2023-10-16	Engle	Added support for DRT 5.42, AEC compression.

Definition in file g2_unpack7.c.

Function Documentation

◆ g2_unpack7()

g2int g2_unpack7	(	unsigned char *	cgrib,
		g2int *	iofst,
		g2int	igdsnum,
		g2int *	igdstmpl,
		g2int	idrsnum,
		g2int *	idrstmpl,
		g2int	ndpts,
		float **	fld
	)

This subroutine unpacks Section 7 (Data Section) of a GRIB2 message.

This function is maintained for backward compatibility. Users may wish to use the newer g2c_unpack7() function instead.

Parameters

cgrib	char array containing Section 7 of the GRIB2 message
iofst	Pointer to a bit offset of the beginning of Section 7 in cgrib. This is updated by this function to reflect the data read in this function. After this function is successfully called, the value pointed to by iofst will be the number of bits to the end of section 7 in cbuf.
igdsnum	Grid Definition Template Number (see Code Table 3.0). (Only used for DRS Template 5.51.)
igdstmpl	Pointer to an integer array containing the data values for the specified Grid Definition Template (N=igdsnum). Each element of this integer array contains an entry (in the order specified) of Grid Definition Template 3.N. (Only used for DRS Template 5.51).
idrsnum	Data Representation Template Number (see Code Table 5.0).
idrstmpl	Pointer to an integer array containing the data values for the specified Data Representation Template (N=idrsnum). Each element of this integer array contains an entry (in the order specified) of Data Representation Template 5.N
ndpts	Number of data points to be unpacked and returned.
fld	Pointer to a float pointer which gets a pointer to an array allocated by this function to hold the unpacked data. This memory must be freed by the caller.

Returns

G2_NO_ERROR No error.
G2_UNPACK_BAD_SEC Array passed had incorrect section number.
G2_UNPACK7_BAD_DRT Unrecognized Data Representation Template.
G2_UNPACK7_WRONG_GDT need one of GDT 3.50 through 3.53 to decode DRT 5.51
G2_UNPACK_NO_MEM Memory allocation error.
G2_UNPACK7_CORRUPT_SEC Corrupt section 7.

Author: Stephen Gilbert

Date: 2002-10-31

Definition at line 214 of file g2_unpack7.c.

References g2c_unpack7_int().

Referenced by g2_getfld().

◆ g2c_unpack7()

int g2c_unpack7	(	unsigned char *	cgrib,
		int	igdsnum,
		int	gds_tmpl_len,
		long long int *	gdstmpl,
		int	idrsnum,
		int	drs_tmpl_len,
		long long int *	drstmpl,
		int	ndpts,
		float *	fld
	)

This subroutine unpacks Section 7 (Data Section) of a GRIB2 message.

This function is the newer version of g2_unpack7().

Parameters

cgrib	char array containing Section 7 of the GRIB2 message
igdsnum	Grid Definition Template Number (see Code Table 3.0). (Only used for DRS Template 5.51.) May be zero for other templates.
gds_tmpl_len	Number of elements in the GDS template.
gdstmpl	Pointer to an integer array containing the data values for the specified Grid Definition Template (N=igdsnum). Each element of this integer array contains an entry (in the order specified) of Grid Definition Template 3.N. (Only used for DRS Template 5.51). May be NULL.
idrsnum	Data Representation Template Number (see Code Table 5.0).
drs_tmpl_len	Number of elements in the DRS template.
drstmpl	Pointer to an integer array containing the data values for the specified Data Representation Template (N=idrsnum). Each element of this integer array contains an entry (in the order specified) of Data Representation Template 5.N
ndpts	Number of data points to be unpacked and returned.
fld	Pointer which the data. Memory must be allocated in advance by caller.

Returns

G2_NO_ERROR No error.
G2_UNPACK_BAD_SEC Array passed had incorrect section number.
G2_UNPACK7_BAD_DRT Unrecognized Data Representation Template.
G2_UNPACK7_WRONG_GDT need one of GDT 3.50 through 3.53 to decode DRT 5.51
G2_UNPACK_NO_MEM Memory allocation error.
G2_UNPACK7_CORRUPT_SEC Corrupt section 7.

Author: Stephen Gilbert

Date: 2002-10-31

Definition at line 259 of file g2_unpack7.c.

References G2C_EINVAL, G2C_ENOMEM, g2c_unpack7_int(), and LOG.

Referenced by g2c_get_prod().

◆ g2c_unpack7_int()

static g2int g2c_unpack7_int	(	unsigned char *	cgrib,
		g2int *	iofst,
		g2int	igdsnum,
		g2int *	igdstmpl,
		g2int	idrsnum,
		g2int *	idrstmpl,
		g2int	ndpts,
		int	v1,
		float **	fld
	)

static

Unpacks Section 7 (Data Section) of a GRIB2 message.

This function is the internal function called by both g2_unpack7() and g2c_unpack7().

Parameters

cgrib	char array containing Section 7 of the GRIB2 message
iofst	Pointer to a bit offset of the beginning of Section 7 in cgrib. This is updated by this function to reflect the data read in this function. After this function is successfully called, the value pointed to by iofst will be the number of bits to the end of section 7 in cbuf.
igdsnum	Grid Definition Template Number (see Code Table 3.0). (Only used for DRS Template 5.51. May be 0 for other templates.)
igdstmpl	Pointer to an integer array containing the data values for the specified Grid Definition Template (N=igdsnum). Each element of this integer array contains an entry (in the order specified) of Grid Definition Template 3.N. (Only used for DRS Template 5.51, may be NULL for other templates).
idrsnum	Data Representation Template Number (see Code Table 5.0).
idrstmpl	Pointer to an integer array containing the data values for the specified Data Representation Template (N=idrsnum). Each element of this integer array contains an entry (in the order specified) of Data Representation Template 5.N
ndpts	Number of data points to be unpacked and returned.
v1	If non-zero, then act like the V1 G2C API. This includes: printing error messages to stderr in the event of error. returning V1 error codes.
fld	Pointer to a float pointer which gets a pointer to an array allocated by this function to hold the unpacked data. This memory must be freed by the caller.

Returns

G2_NO_ERROR No error.
G2_UNPACK_BAD_SEC Array passed had incorrect section number.
G2_UNPACK7_BAD_DRT Unrecognized Data Representation Template.
G2_UNPACK7_WRONG_GDT need one of GDT 3.50 through 3.53 to decode DRT 5.51
G2_UNPACK_NO_MEM Memory allocation error.
G2_UNPACK7_CORRUPT_SEC Corrupt section 7.

Author: Stephen Gilbert

Date: 2002-10-31

Definition at line 67 of file g2_unpack7.c.

References aecunpack(), comunpack(), G2_NO_ERROR, G2_UNPACK7_BAD_DRT, G2_UNPACK7_CORRUPT_SEC, G2_UNPACK7_WRONG_GDT, G2_UNPACK_BAD_SEC, G2_UNPACK_NO_MEM, gbit(), jpcunpack(), LOG, pngunpack(), rdieee(), simunpack(), and specunpack().

Referenced by g2_unpack7(), and g2c_unpack7().

Functions

Detailed Description

Program History Log

Function Documentation

◆ g2_unpack7()

◆ g2c_unpack7()

◆ g2c_unpack7_int()