Connect C++ to Running MATLAB Session

You can connect the C++ engine to shared MATLAB^® sessions that are running on the local machine. To connect to a shared MATLAB session:

Start MATLAB as a shared session, or make a running MATLAB process shared using the matlab.engine.shareEngine MATLAB function.
Find the names of the MATLAB shared sessions using matlab::engine::findMATLAB or matlab::engine::findMATLABAsync.
Pass a matlab::engine::String containing the name of the shared MATLAB session to the matlab::engine::connectMATLAB or matlab::engine::connectMATLABAsync member function. These functions connect the C++ engine to the shared session.

If you do not specify the name of a shared MATLAB session when calling matlab::engine::connectMATLAB or matlab::engine::connectMATLABAsync, the engine uses the first shared MATLAB session created. If there are no shared MATLAB sessions available, the engine creates a shared MATLAB session and connects to this session.

For information on how to setup and build C++ engine programs, see Build C++ Engine Programs.

Connect to Shared MATLAB

This sample code connects to the first shared MATLAB session found.

#include "MatlabEngine.hpp"

void syncConnect() {
    using namespace matlab::engine;

    // Connect to shared MATLAB session
    std::unique_ptr<MATLABEngine> matlabPtr = connectMATLAB();
}

Connect to Shared MATLAB Asynchronously

This sample code connects to the first shared MATLAB session found asynchronously.

#include "MatlabEngine.hpp"

void asyncConnect() {
    using namespace matlab::engine;

    // Find and connect to shared MATLAB session
    FutureResult<std::unique_ptr<MATLABEngine>> futureMATLAB = connectMATLABAsync();
        ...
    std::unique_ptr<MATLABEngine> matlabPtr = futureMATLAB.get();
}

Specify Name of Shared Session

You can specify the name of the shared MATLAB session when you execute the matlab.engine.shareEngine MATLAB function. Doing so eliminates the need to use matlab::engine::findMATLAB or matlab::engine::findMATLABAsync to find the name.

For example, start MATLAB and name the shared session myMatlabEngine.

matlab -r "matlab.engine.shareEngine('myMatlabEngine')"

This sample code connects to the MATLAB session named myMatlabEngine from C++.

Note

Start the named MATLAB session before connecting from the C++ code.

#include "MatlabEngine.hpp"

void connectToML() {
    using namespace matlab::engine;

    // Connect to named shared MATLAB session started as:
    // matlab -r "matlab.engine.shareEngine('myMatlabEngine')"
    std::unique_ptr<MATLABEngine> matlabPtr = connectMATLAB(u"myMatlabEngine");
}

Find and Connect to Named Shared Session

To connect to a named MATLAB shared session, use matlab::engine::findMATLAB or matlab::engine::findMATLABAsync to find the names of all available named MATLAB shared sessions.

This sample code tries to find a MATLAB shared session named myMatlabEngine and connects to it if the session is found.

void findNConnect() {
    using namespace matlab::engine;

    // Find and connect to shared MATLAB session
    std::unique_ptr<MATLABEngine> matlabPtr;
    std::vector<String> names = findMATLAB();
    std::vector<String>::iterator it;
    it = std::find(names.begin(), names.end(), u"myMatlabEngine");
    if (it != names.end()) {
        matlabPtr = connectMATLAB(*it);
    }

    // Determine if engine connected
    if (matlabPtr){
        matlab::data::ArrayFactory factory;
        matlab::data::CharArray arg = factory.createCharArray("-release");
        matlab::data::CharArray version = matlabPtr->feval(u"version", arg);
        std::cout << "Connected to: " << version.toAscii() << std::endl;
    }
    else {
        std::cout << "myMatlabEngine not found" << std::endl;
    }
}

Documentation