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.Dd April 21, 2011
.Dt MAT_VARREAD 3
.Os
.Sh NAME
.Nm Mat_VarRead
.Nd Reads the information and data for a specific variable in a MATLAB MAT file.
.Sh SYNOPSIS
.Fd #include <matio.h>
.Ft matvar_t *
.Fo Mat_VarRead
.Fa "mat_t *matfp"
.Fa "const char *name"
.Fc
.Sh DESCRIPTION
The
.Fn Mat_VarRead
function reads the information and data for the variable
.Fa name
in the open MAT file.
.Sh RETURN VALUES
If the variable was found in the MAT file and successfully read, a pointer to
the MATLAB variable structure is returned. If the variable was not found, or
there was an error reading the variable, NULL is returned.
.Sh EXAMPLES
This example program opens a MAT file named by the first argument to the
program, and reads a variable named
.Em x
from the file.
The matio function Mat_VarPrint is used to print the information and data from
the file.
.Bd -literal
#include "matio.h"

int
main(int argc,char **argv)
{
    mat_t    *matfp;
    matvar_t *matvar;

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

    matvar = Mat_VarRead(matfp,"x");
    if ( NULL != matvar ) {
        Mat_VarPrint(matvar);
        Mat_VarFree(matvar);
    }

    Mat_Close(matfp);
    return EXIT_SUCCESS;
}

.Ed
.Sh SEE ALSO
.Xr Mat_VarReadInfo 3 ,
.Xr Mat_VarReadNext 3 ,
.Xr Mat_VarPrint 3