}

  public void testVertical_nanX() {
    assertThrows(IllegalArgumentException.class, () -> LinearTransformation.vertical(Double.NaN));
  }

  public void testHorizontal_regular() {
    double y = 1.2;
    LinearTransformation transformation = LinearTransformation.horizontal(y);
    assertHorizontalLinearTransformation(transformation, y);
  }

  }

  public void testVertical_nanX() {
    assertThrows(IllegalArgumentException.class, () -> LinearTransformation.vertical(Double.NaN));
  }

  public void testHorizontal_regular() {
    double y = 1.2;
    LinearTransformation transformation = LinearTransformation.horizontal(y);
    assertHorizontalLinearTransformation(transformation, y);
  }