Method data

tests/test_ndarray.cpp:659–659

        MyArray() { d = new double[5] { 0.0, 1.0, 2.0, 3.0, 4.0 }; }
        ~MyArray() { delete[] d; }
        double* data() const { return d; }
        void mutate() { for (int i = 0; i < 5; ++i) d[i] += 0.5; }
    };