mxGetElementSize (External Interfaces Reference)

Get number of bytes required to store each data element

C Syntax

#include "matrix.h"
int mxGetElementSize(const mxArray *array_ptr);

Arguments

array_ptr
Pointer to an mxArray.

Returns

The number of bytes required to store one element of the specified mxArray, if successful. Returns 0 on failure. The primary reason for failure is that array_ptr points to an mxArray having an unrecognized class. If array_ptr points to a cell mxArray or a structure mxArray, then mxGetElementSize returns the size of a pointer (not the size of all the elements in each cell or structure field).

Description

Call mxGetElementSize to determine the number of bytes in each data element of the mxArray. For example, if the mxClassID of an mxArray is mxINT16_CLASS, then the mxArray stores each data element as a 16-bit (2 byte) signed integer. Thus, mxGetElementSize returns 2.

mxGetElementSize is particularly helpful when using a non-MATLAB routine to manipulate data elements. For example, memcpy requires (for its third argument) the size of the elements you intend to copy.

Examples

See doubleelement.c and phonebook.c in the refbook subdirectory of the examples directory.

See Also

mxGetM, mxGetN

mxGetDimensions mxGetEps