Mat_VarReadNextInfo(3)

MAT_VARREADNEXTINFO(3) Library Functions Manual MAT_VARREADNEXTINFO(3)

NAME

Mat_VarReadNextInfo — Reads the information for the next variable in a MATLAB MAT file.

SYNOPSIS

#include <matio.h>

matvar_t *

Mat_VarReadNextInfo(mat_t *matfp);

DESCRIPTION

The Mat_VarReadNextInfo() function reads the information for the next variable stored in the open MAT file.

RETURN VALUES

If there is another variable in the MAT file and is read successfully, a pointer to the MATLAB variable structure is returned. If there are no more variables, or there was an error reading the variable, NULL is returned.

EXAMPLES

This example program opens a MAT file named by the first argument to the program, and uses Mat_VarReadNextInfo() to read the information about each variable in the file. For each variable read, the name, size, and class are printed in a format similar to the MATLAB whos command.

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

static char *mxclass[17] = {"cell", "struct", "object", "char", "sparse",
"double", "single", "int8", "uint8", "int16",
"uint16", "int32", "uint32", "int64", "uint64",
"function", "opaque"
};

int
main(int argc, char **argv)
{
mat_t *matfp;
matvar_t *matvar;
char size[32] = {’ ’,};

matfp = Mat_Open(argv[1], MAT_ACC_RDONLY);
if ( NULL == matfp ) {
fprintf(stderr, "Error opening MAT file %s0, argv[1]);
return EXIT_FAILURE;
}

printf("%-20s %-10s %-10s %-18s0, "Name", "Size",
"Bytes", "Class");
while ( NULL != (matvar = Mat_VarReadNextInfo(matfp)) ) {
printf("%-20s", matvar->name);
if ( matvar->rank > 0 ) {
int cnt = 0;
int i;
printf("%8d", matvar->dims[0]);
for ( i = 1; i < matvar->rank; i++ ) {
if ( ceil(log10(matvar->dims[i])) + 1 < 32 )
cnt += sprintf(size + cnt, "x%d", matvar->dims[i]);
}
printf("%-10s", size);
} else {
printf(" ");
}
printf(" %-18s0, mxclass[matvar->class_type - 1]);

Mat_VarFree(matvar);
}

Mat_Close(matfp);
return EXIT_SUCCESS;
}

SEE ALSO

Mat_VarRead(3), Mat_VarReadInfo(3), Mat_VarReadNext(3) GNU September 12, 2019 MAT_VARREADNEXTINFO(3)