mxSetImagData (C)

Set imaginary data elements in numeric mxArray

mxSetImagData is not available in the interleaved complex API. Use typed, data-access functions instead. For more information, see Version History.

C Syntax

#include "matrix.h"
void mxSetImagData(mxArray *pm, void *pi);

Description

The mxSetImagData function is similar to mxSetPi, except that in C, its pi argument is a void *. Use this function on numeric arrays with contents other than double.

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

Input Arguments

pm — Pointer to MATLAB^® array

mxArray*

Pointer to a MATLAB array, specified as mxArray *.

pi — Pointer to complex data array

void*

Pointer to the complex data array within an mxArray, specified as void *. Each element in the array contains the imaginary 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 pi points to static memory, then memory errors result when the array is destroyed.

Version History

Introduced before R2006a

R2018a: Do not use separate complex API

MathWorks recommends that you create MEX files and update existing MEX files to use the typed, data-access functions in the interleaved complex API. These functions verify that the input array is complex and of the correct type for the function. 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

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

R2018a: Error building mxSetImagData with interleaved complex API

The mxSetImagData function is only available in the separate complex API. To build myMexFile.c using this function, type:

mex -R2017b myMexFile.c

Existing MEX files built with this function continue to run.