Function custom_matrix_expressions_example

examples/matrix_expressions_ex.cpp:348–403

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void custom_matrix_expressions_example(
)
{
    matrix<double> x(2,3);
    x = 1, 1, 1,
        2, 2, 2;

    cout << x << endl;

    // Finally, let's use the matrix expressions we defined above.

    // prints the transpose of x
    cout << example_trans(x) << endl;

    // prints this:
    //   11 11 11
    //   12 12 12
    cout << add_scalar(x, 10) << endl;


    // matrix expressions can be nested, even the user defined ones.
    // the following statement prints this:
    //   11 12 
    //   11 12 
    //   11 12 
    cout << example_trans(add_scalar(x, 10)) << endl;

    // Since we setup the alias detection correctly we can even do this:
    x = example_trans(add_scalar(x, 10));
    cout << "new x:\n" << x << endl;

    cout << "Do some testing with the example_vector_to_matrix() function: " << endl;
    std::vector<float> vect;
    vect.push_back(1);
    vect.push_back(3);
    vect.push_back(5);

    // Now let's treat our std::vector like a matrix and print some things.
    cout << example_vector_to_matrix(vect) << endl;
    cout << add_scalar(example_vector_to_matrix(vect), 10) << endl;



    /*
        As an aside, note that dlib contains functions equivalent to the ones we 
        defined above.  They are:
            - dlib::trans()
            - dlib::mat() (converts things into matrices)
            - operator+ (e.g. you can say my_mat + 1)


        Also, if you are going to be creating your own matrix expression you should also
        look through the matrix code in the dlib/matrix folder.  There you will find 
        many other examples of matrix expressions. 
    */
}

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