User`s manual

2 Creating C Language MEX-Files

2-34

* This is a MEX-file for MATLAB.

*============================================================*/

#include "mex.h"

#define MAX 1000

/* Subroutine for filling up data */

void fill( double *pr, int *pm, int *pn, int max )

{

int i;

/* You can fill up to max elements, so (*pr) <= max. */

*pm = max/2;

*pn = 1;

for(i = 0; i < (*pm); i++)

pr[i] = i*(4*3.14159/max);

}

/* Gateway function */

void mexFunction( int nlhs, mxArray *plhs[],

int nrhs, const mxArray *prhs[] )

{

int m, n, max = MAX;

mxArray *rhs[1], *lhs[1];

rhs[0] = mxCreateDoubleMatrix(max, 1, mxREAL);

/* Pass the pointers and let fill() fill up data. */

fill(mxGetPr(rhs[0]), &m, &n, MAX);

mxSetM(rhs[0], m);

mxSetN(rhs[0], n);

/* Get the sin wave and plot it. */

mexCallMATLAB(1, lhs, 1, rhs, "sin");

mexCallMATLAB(0, NULL, 1, lhs, "plot");

/* Clean up allocated memory. */

mxDestroyArray(rhs[0]);