Programming and Graphics

296 Introduction to C++ Programming and Graphics

//--- Matlab session:

engEvalString(lva, "b");

cout << buffer; // transfer back the matlab response

//--- End the session:

engClose(lva);

return 0;

}

The output of the code is:

>>

b=

5

Two-dimensional graph

The following code contained in the filemplot2d.ccgenerates data and
prepares a two-dimensional plot usingMatlabgraphics functions:

#include <iostream>

#include "engine.h"

using namespace std;

int main()

{

//--- Define data:

const short sdata = 5;

double x[sdata] ={0.0, 0.1, 0.5, 0.8, 0.9};

double y[sdata] ={0.0, 0.2, 0.3, 0.4, 0.42};

//--- Start a Matlab session:

Engine * iams = engOpen("matlab -nojvm");

/*--- Reserve the array ‘‘hronos’’

Copy into memory

Transfer the data */

mxArray * hronos = mxCreateDoubleMatrix(1, sdata, mxREAL);

memcpy((void *)mxGetPr(hronos), (void *)x, sizeof(x));