@Test
public void calculatesProduct() {

    final Double[] coords = DotTest.doubles(DotTest.COORDS_LENGTH);
    final Vect<Double> vecta = new DblVect(coords);
    final Vect<Double> vectb = new DblVect(coords);
    Double result = 0.;
    for (final Double coord : coords) {
        result += coord * coord;
    }
    MatcherAssert.assertThat(
        new Equals<>(
            new Dot().product(vecta, vectb), new Scalar.Default<>(result)
        ).resolve(new Decimal()),
        Matchers.equalTo(true)
    );
}