mxSetPr (C)

(Not recommended) Set real data elements in mxDOUBLE_CLASS array

mxSetPr is not available in the interleaved complex API. Use mxSetDoubles or mxSetComplexDoubles instead. For more information, see Version History.

C Syntax

#include "matrix.h"
void mxSetPr(mxArray *pm, double *pr);

Description

The mxSetPr function sets the real data of a real mxDOUBLE_CLASS array pm. If you build with the interleaved complex API (mex -R2018a option) and pm is complex, then the function terminates the MEX file and returns control to the MATLAB^® prompt. In a non-MEX file application, the function returns NULL.

Call mxIsDouble to validate the mxArray type. Call mxIsComplex to determine whether the data is real.

All mxCreate* functions allocate heap space to hold data. Therefore, you do not ordinarily use this function to initialize the real elements of an array. Instead, call this function to replace the existing values with new values.

The mxSetPr function does not free memory allocated for existing data. To free existing memory, call mxFree on the pointer returned by mxGetPr.

Input Arguments

pm — Pointer to MATLAB array

mxArray *

Pointer to a MATLAB array of type mxDOUBLE_CLASS, specified as mxArray *.

pr — Pointer to data array

double *

Pointer to the first mxDouble element of the real part of the data array within an mxArray, specified as double *. Each element in the array contains the real component of a value.

The array must be in dynamic memory. Call mxCalloc to allocate this memory. Do not use the ANSI^® C calloc function, which can cause memory alignment issues leading to program termination. If pr points to static memory, then memory leaks and other memory errors can result.

Version History

Introduced before R2006a

R2018a: Do not use separate complex API

Use the mxSetDoubles function in the interleaved complex API for real arrays of type mxDOUBLE_CLASS. Use mxSetComplexDoubles for complex arrays of type mxDOUBLE_CLASS. These functions validate the type and complexity of the input.

MathWorks recommends that you create MEX files and update existing MEX files to use the typed, data-access functions in the interleaved complex API. For more information, see:

• Typed Data Access in C MEX Files

• MATLAB Support for Interleaved Complex API in MEX Functions

• Upgrade MEX Files to Use Interleaved Complex API

• Example fulltosparse.c

To build the MEX file, call mex with the -R2018a option.

R2018a: Runtime error calling mxSetPr on complex mxArrays in applications built with interleaved complex API

Use the mxSetComplexDoubles function instead of mxSetPr and mxGetPi. For an example showing how to update code that uses mxSetPr, see mxsetnzmax.c.