Provided by: libgetdata-doc_0.10.0-3build2_all
NAME
gd_native_type — returns the native data type of a field in a Dirfile
SYNOPSIS
#include <getdata.h> gd_type_t gd_native_type(DIRFILE *dirfile, const char *field_code);
DESCRIPTION
The gd_native_type() function queries a dirfile(5) database specified by dirfile and determines the native type of data specified by field_code, which may contain a representation suffix. The dirfile argument must point to a valid DIRFILE object previously created by a call to gd_open(3). The native data type of a field of a given entry type is calculated as: BIT INDEX GD_UINT64; CONST CARRAY the data type of the field; DIVIDE MULTIPLY if either input field is complex valued: GD_COMPLEX128, otherwise: GD_FLOAT64; INDIR the data type of the input CARRAY; LINCOM POLYNOM if any of the scalar parameters is complex valued, or if the native data type of any of the input fields is complex valued: GD_COMPLEX128, otherwise: GD_FLOAT64; LINTERP if the look-up table is complex valued: GD_COMPLEX128, otherwise: GD_FLOAT64; MPLEX WINDOW the native data type of the data field; PHASE the native data type of the input field; RAW the data type of the raw data on disk; RECIP if the dividend or the native data type of the input field is complex valued: GD_COMPLEX128, otherwise: GD_FLOAT64; SARRAY SINDIR STRING GD_STRING; SBIT GD_INT64. Furthermore, if the supplied field_code contains a representation suffix, and the native data type of the field is complex valued, the native type returned will be the corresponding real valued type.
RETURN VALUE
Upon successful completion, gd_native_type() returns the native data type of the field code specified. This will equal one of the symbols: GD_UINT8, GD_INT8, GD_UINT16, GD_INT16, GD_UINT32, GD_INT32, GD_FLOAT32, GD_FLOAT64, GD_COMPLEX64, GD_COMPLEX128, GD_STRING. The meanings of these symbols are explained in the gd_getdata(3) manual page. On error, this function returns GD_UNKNOWN and stores a negative-valued error code in the DIRFILE object which may be retrieved by a subsequent call to gd_error(3). Possible error codes are: GD_E_ALLOC The library was unable to allocate memory. GD_E_BAD_CODE The field specified by field_code or one of the fields it uses as input was not found in the database. GD_E_BAD_DIRFILE The supplied dirfile was invalid. GD_E_DIMENSION A scalar field was found where a vector field was expected. GD_E_IO An error occurred while trying to read a LINTERP table from disk. GD_E_LUT A LINTERP table was malformed. GD_E_RECURSE_LEVEL Too many levels of recursion were encountered while trying to resolve field_code. This usually indicates a circular dependency in field specification in the dirfile. A descriptive error string for the error may be obtained by calling gd_error_string(3).
HISTORY
The get_native_type() function appeared in GetData-0.6.0. The return type for STRING fields was GD_NULL. In GetData-0.7.0, this function was renamed to gd_native_type(). Before GetData-0.10.0, the return type for STRING fields was GD_NULL.
SEE ALSO
gd_error(3), gd_error_string(3) gd_getdata(3), gd_open(3), dirfile(5)