public void self_angle_is_zero()
{
var vector = new Vector4D(10, 57, -9, 10);
var expected = 0.0;
var actual = vector.GetAngleBetween(vector);
Assert.Equal(expected, actual);
}
public void example_2()
{
var left = new Vector4D(1, 3, 4, 9);
var right = new Vector4D(-2, 5.6, -9, 0.1);
var expected = 1.7537363654297111;
var actual = left.GetAngleBetween(right);
Assert.Equal(expected, actual, 10);
}
public void example_1()
{
var left = new Vector4D(1, 0, 0, 0);
var right = new Vector4D(1, 0, 1, 0);
var expected = Math.Acos(1.0 / Math.Sqrt(2.0));
var actual = left.GetAngleBetween(right);
Assert.Equal(expected, actual, 10);
}
public void opposite_vector_angle_is_pi()
{
var left = new Vector4D(14, 98, -19, 88);
var right = left.GetNegative();
var expected = Math.PI;
var actual = left.GetAngleBetween(right);
Assert.Equal(expected, actual, 10);
}
public void right_angle_is_half_pi()
{
var left = new Vector4D(1, 0, 1, 0);
var right = new Vector4D(0, 1, 0, 1);
var expected = Math.PI / 2.0;
var actual = left.GetAngleBetween(right);
Assert.Equal(expected, actual, 10);
}