MCordingley\LinearAlgebraTest\MatrixTest::testDiagonal PHP Method

    public function testDiagonal()
    {
        $matrix = new Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]);
        $diagonal = $matrix->diagonal();
        static::assertEquals(1, $diagonal->get(0, 0));
        static::assertEquals(0, $diagonal->get(0, 1));
        static::assertEquals(0, $diagonal->get(0, 2));
        static::assertEquals(0, $diagonal->get(1, 0));
        static::assertEquals(5, $diagonal->get(1, 1));
        static::assertEquals(0, $diagonal->get(1, 2));
        static::assertEquals(0, $diagonal->get(2, 0));
        static::assertEquals(0, $diagonal->get(2, 1));
        static::assertEquals(9, $diagonal->get(2, 2));
    }