mxSetDimensions (External Interfaces Reference)

Modify number of dimensions and size of each dimension

C Syntax

#include "matrix.h"
int mxSetDimensions(mxArray *array_ptr, const int *dims, int ndim);

Arguments

array_ptr
Pointer to an mxArray.

dims
The dimensions array. Each element in the dimensions array contains the size of the array in that dimension. For example, setting dims[0] to 5 and dims[1] to 7 establishes a 5-by-7 mxArray. In most cases, there should be ndim elements in the dims array.

ndim
The desired number of dimensions.

Returns

0 on success, and 1 on failure. mxSetDimensions allocates heap space to hold the input size array. So it is possible (though extremely unlikely) that increasing the number of dimensions can cause the system to run out of heap space.

Description

Call mxSetDimensions to reshape an existing mxArray. mxSetDimensions is similar to mxSetM and mxSetN; however, mxSetDimensions provides greater control for reshaping mxArrays that have more than two-dimensions.

mxSetDimensions does not allocate or deallocate any space for the pr or pi arrays. Consequently, if your call to mxSetDimensions increases the number of elements in the mxArray, then you must enlarge the pr (and pi, if it exists) arrays accordingly.

If your call to mxSetDimensions reduces the number of elements in the mxArray, then you can optionally reduce the size of the pr and pi arrays using mxRealloc.

Any trailing singleton dimensions specified in the dims argument are automatically removed from the resulting array. For example, if ndim equals 5 and dims equals [4 1 7 1 1], the resulting array is given the dimensions 4-by-1-by-7.

Examples

See mxsetdimensions.c in the mx subdirectory of the examples directory.

mxSetData mxSetField