public void subtracting_null_vector_throws()
{
var left = new VectorD(3);
VectorD right = null;
Assert.Throws <ArgumentNullException>(() => left.Subtract(right));
}
public void subtracting_vectors_of_different_size_throws()
{
var left = new VectorD(3);
var right = new VectorD(4);
Assert.NotEqual(left.Dimensions, right.Dimensions);
Assert.Throws <ArgumentOutOfRangeException>(() => left.Subtract(right));
}
public void subtracting_vectors_leaves_right_unchanged()
{
var left = new VectorD(3);
left.Set(0, 1);
left.Set(1, 10);
left.Set(2, 6);
var right = new VectorD(3);
right.Set(0, 10);
right.Set(1, 3);
right.Set(2, 1);
var expectedRight = new VectorD(right);
left.Subtract(right);
Assert.Equal(expectedRight, right);
}
public void subtracting_vector_subtracts_from_components()
{
var actual = new VectorD(3);
actual.Set(0, 1);
actual.Set(1, 10);
actual.Set(2, 6);
var right = new VectorD(3);
right.Set(0, 10);
right.Set(1, 3);
right.Set(2, 1);
var expected = new VectorD(3);
expected.Set(0, -9);
expected.Set(1, 7);
expected.Set(2, 5);
actual.Subtract(right);
Assert.Equal(expected, actual);
}