C + + invoke MATLAB instance

This code is the process by which C + + calls the Matab engine, the purpose of the code is simple, create a vector array in C + +, and then unit the vector array. The purpose of writing this code is to learn some data interaction between C + + and MATLAB for future reference.

#include <iostream>

#include <cstdio>

#include <vector>

#include <math.h>

#include <time.h>

#include "Engine.h"

#include<Eigen/Dense>

using namespace Eigen;

using namespace STD;

vector<double> veca;

void Createa (int m );

int Main ()

{

Const int num = 10;

Createa ( num ); //Create original matrix Veca

Double * pa = new double[10];

for ( int i = 0; i < num; I+ +)

{

PA [i] = Veca[i];

}

Engine * m_engine; //matlab engine

m_engine = NULL; //Initialize MATLAB engine

if ((! m_engine &&! (m_engine = engopen(NULL)))) //Open the Amatlab engine and fail to exit

{

return -1;

}

engsetvisible (m_engine, 1); //Set the visibility of the Matlab window when it is called, A1 when it is visible?

//Transfer the data that needs to be calculated into Matlab

Mxarray *veca= Mxcreatedoublematrix(1, mxreal); //Create a real number of 10 rows and 1 columns, the group array type is unique to Matlab

memcpy (void *) mxgetpr(veca), (void *) PA, ten * sizeof(double )); //Transfer data from D in C + + to Matlab

engputvariable (m_engine, "Vec", Veca); //Assignment statement, VEC is the input parameter in MATLAB code Y,VECA is an incoming parameter of C + +

//buffer is used to receive debugging information, when the MATLAB code is wrong, you can output buffer to view the error message

Char Buffer [255];

Buffer [254] = '+ ';

Engoutputbuffer (m_engine, buffer, 255);

engevalstring (m_engine, "CD (' D:\\code\\testeigen\\testeigen\\mat_code ')"); //Open the folder where the MATLAB code is located, notice that the path is double- backslash

engevalstring (m_engine,"Normalv = Normalizevec (VEC);"); //This is a call statement in MATLAB, note that the. m file name of MATLAB is consistent with the name of the called function, otherwise the function to be called is not found

printf ("%s", buffer); //When the MATLAB code goes wrong, it is used to output debugging information

the results of MATLAB are then passed back to C + +

Mxarray * mvec = NULL; //Also declare a type of bursts in MATLAB

Mvec = enggetvariable(m_engine, "Normalv");

Double * Cvec= NULL; //Declare a pointer in C + +

Cvec= (double*)mxgetdata(mvec); //Assign data from Matlab to data in C + +

for ( int i = 0; i<num; I+ +)

{

cout<< cvec[i] << "";

}

Mxdestroyarray (Veca); //Destroy MATLAB array

Mxdestroyarray (Mvec);

return 0;

system ("Pause" );

}

void Createa (int m )

{

Srand (time (NULL));

for ( int i = 0; I < m; I+ +)

{

Veca. push_back (Rand()%4 + 1);

cout << veca[i]<<"";

}

cout <<endl<<"-----------------------"<<Endl;

}

Output Result:

Matlab code:

The% function is to realize the unit of a vector

function Normalv = Normalizevec (VEC)

Normalv = vec/sqrt (sum (vec.^2, 2));

End

When an error occurs, you see the following message,

Then know that the Normaozeve function is undefined, and that the call statement is wrong.

C + + calls Matlab instance