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mxGetNumberOfFields (C and Fortran)

Number of fields in structure array

C Syntax

#include "matrix.h"
int mxGetNumberOfFields(const mxArray *pm);

Fortran Syntax

#include "fintrf.h"
integer*4 mxGetNumberOfFields(pm)
mwPointer pm



Pointer to a structure mxArray


Number of fields, on success. Returns 0 on failure. The most common cause of failure is that pm is not a structure mxArray. Call mxIsStruct to determine whether pm is a structure.


Call mxGetNumberOfFields to determine how many fields are in the specified structure mxArray.

Once you know the number of fields in a structure, you can loop through every field to set or to get field values.


See the following examples in matlabroot/extern/examples/refbook.

See the following examples in matlabroot/extern/examples/mx.

See the following examples in matlabroot/extern/examples/mex.

Introduced before R2006a

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