{

// Prepare data

int ncols = 500, nrows = 300;

std::vector<float> z(ncols * nrows);

for (int j=0; j<nrows; ++j) {

for (int i=0; i<ncols; ++i) {

z.at(ncols * j + i) = std::sin(std::hypot(i - ncols/2, j - nrows/2));

}

}

const float* zptr = &(z[0]);

const int colors = 1;

plt::title("My matrix");

PyObject* mat;

plt::imshow(zptr, nrows, ncols, colors, {}, &mat);

plt::colorbar(mat);

// Show plots

plt::show();

plt::close();

Py_DECREF(mat);