ribbon_4.cpp

#include <cmath>
#include <matplot/matplot.h>

int main() {
    using namespace matplot;

    auto rastrigin = [](double x, double y) {
        return 10 * 2 + pow(x,2) - 10 * cos(2*pi*x) + pow(y,2) - 10 * cos(2*pi*y);
    };

    auto [X,Y] = meshgrid(iota(-5,1.,5),iota(-5,.1,5));
    auto Z = transform(X,Y,rastrigin);
    ribbon(X,Y,Z)->face_alpha(0.8);

    wait();
    return 0;
}