def test_length(self):
"""Get/set the vector length."""
v = Vector2D(1.2, -3)
# get length
r = sqrt(1.2 * 1.2 + 3 * 3)
self.assertAlmostEqual(v.length,
r,
places=14,
msg="Vector2D returned incorrect length.")
# set length
v.length = 10.0
rx = 1.2 / sqrt(1.2 * 1.2 + 3 * 3) * 10
ry = -3 / sqrt(1.2 * 1.2 + 3 * 3) * 10
self.assertAlmostEqual(v.x, rx, 14,
"Vector2D length was not set correctly [X].")
self.assertAlmostEqual(v.y, ry, 14,
"Vector2D length was not set correctly [Y].")
# trying to rescale a zero length vector should raise a ZeroDivisionError
v = Vector2D(0, 0)
with self.assertRaises(
ZeroDivisionError,
msg=
"Adjusting length of zero length vector did not raise a ZeroDivisionError."
):
v.length = 10.0
def test_cross_product(self):
"""Testing cross product."""
# raysect uses a right handed coordinate system
x = Vector2D(1, 0)
y = Vector2D(0, 1)
# orthogonal
r = x.cross(y)
self.assertEqual(r, 1.0, "Cross product failed.")
# orthonormal
r = x.cross(x)
self.assertEqual(r, 0.0, "Cross product failed.")
# arbitrary Vector2D x Vector2D
a = Vector2D(4, 2)
b = Vector2D(-1, 2)
r1 = a.cross(b)
r2 = b.cross(a)
self.assertEqual(r1, 4 * 2 - 2 * -1, "Cross product failed.")
self.assertEqual(r2, 2 * -1 - 4 * 2, "Cross product failed.")
def test_dot_product(self):
"""Testing dot product."""
x = Vector2D(1, 0)
y = Vector2D(0, 1)
# orthogonal
self.assertEqual(
x.dot(y), 0.0,
"Dot product of orthogonal vectors does not equal 0.0.")
# orthonormal
self.assertEqual(
x.dot(x), 1.0,
"Dot product of orthonormal vectors does not equal 1.0.")
self.assertEqual(
y.dot(y), 1.0,
"Dot product of orthonormal vectors does not equal 1.0.")
# arbitrary
a = Vector2D(4, 2)
b = Vector2D(-1, 2)
self.assertEqual(
a.dot(b), 4 * -1 + 2 * 2,
"Dot product of two arbitrary vectors gives the wrong value.")
self.assertEqual(a.dot(b), b.dot(a), "a.b does not equal b.a.")
def test_subtract(self):
"""Subtract operator."""
# Vector2D - Vector2D, returns Vector2D
a = Vector2D(-1.4, 0.2)
b = Vector2D(0.7, -64.0)
r = a - b
self.assertTrue(isinstance(r, Vector2D),
"Vector2D - Vector2D did not return a Vector2D.")
self.assertEqual(r.x, -1.4 - 0.7, "Vector2D - Vector2D failed [X].")
self.assertEqual(r.y, 0.2 + 64.0, "Vector2D - Vector2D failed [Y].")
def test_add(self):
"""Add operator."""
# Vector2D + Vector2D, returns Vector2D
a = Vector2D(-1.4, 0.2)
b = Vector2D(0.7, -64.0)
r = a + b
self.assertTrue(isinstance(r, Vector2D),
"Vector2D + Vector2D did not return a Vector2D.")
self.assertEqual(r.x, -1.4 + 0.7, "Vector2D + Vector2D failed [X].")
self.assertEqual(r.y, 0.2 - 64.0, "Vector2D + Vector2D failed [Y].")
def test_divide(self):
"""Division operator."""
v = Vector2D(-1.4, 0.2)
# Vector2D / c, returns Vector2D
r = v / 5.3
self.assertTrue(isinstance(r, Vector2D),
"Vector2D * c did not return a Vector2D.")
self.assertEqual(r.x, -1.4 / 5.3, "Vector2D * c failed [X].")
self.assertEqual(r.y, 0.20 / 5.3, "Vector2D * c failed [Y].")
# dividing by zero should raise a ZeroDivisionError
with self.assertRaises(
ZeroDivisionError,
msg="Dividing by zero did not raise a ZeroDivisionError."):
r = v / 0.0
# any other division operations should raise TypeError
with self.assertRaises(
TypeError,
msg="Undefined division did not raised a TypeError."):
r = 54.2 / v
with self.assertRaises(
TypeError,
msg="Undefined division did not raised a TypeError."):
r = v / v
def test_iter(self):
"""Obtain values by iteration."""
v = Vector2D(2.5, 6.7)
l = list(v)
self.assertEqual(
len(l), 2,
"Iteration failed to return the correct number of items.")
self.assertEqual(l[0], 2.5, "Iteration failed [X].")
self.assertEqual(l[1], 6.7, "Iteration failed [Y].")
def test_y(self):
"""Get/set y co-ordinate."""
v = Vector2D(2.5, 6.7)
# get y attribute
self.assertEqual(v.y, 6.7, "Getting y attribute failed.")
# set y attribute
v.y = -7.1
self.assertEqual(v.y, -7.1, "Setting y attribute failed.")
def test_x(self):
"""Get/set x co-ordinate."""
v = Vector2D(2.5, 6.7)
# get x attribute
self.assertEqual(v.x, 2.5, "Getting x attribute failed.")
# set x attribute
v.x = 10.0
self.assertEqual(v.x, 10.0, "Setting x attribute failed.")
def test_copy(self):
"""Testing method copy()."""
v = Vector2D(1.0, 2.0)
r = v.copy()
# check a new instance has been created by modifying the original
v.x = 5.0
v.y = 6.0
self.assertEqual(r.x, 1.0, "Copy failed [X].")
self.assertEqual(r.y, 2.0, "Copy failed [Y].")
def test_normalise(self):
"""Testing normalise() method."""
# normalise
v = Vector2D(23.2, 0.12)
r = v.normalise()
l = v.length
self.assertTrue(isinstance(r, Vector2D),
"Normalise did not return a Vector2D.")
self.assertAlmostEqual(r.x, 23.2 / l, 14, "Normalise failed [X].")
self.assertAlmostEqual(r.y, 0.12 / l, 14, "Normalise failed [Y].")
# attempting to normalise a zero length vector should raise a ZeroDivisionError
v = Vector2D(0.0, 0.0)
with self.assertRaises(
ZeroDivisionError,
msg=
"Normalising a zero length vector did not raise a ZeroDivisionError."
):
r = v.normalise()
def test_multiply(self):
"""Multiply operator."""
v = Vector2D(-1.4, 0.2)
# c * Vector2D, returns Vector2D
r = 0.23 * v
self.assertTrue(isinstance(r, Vector2D),
"c * Vector2D did not return a Vector2D.")
self.assertEqual(r.x, 0.23 * -1.4, "c * Vector2D failed [X].")
self.assertEqual(r.y, 0.23 * 0.20, "c * Vector2D failed [Y].")
# Vector2D * c, returns Vector2D
r = v * -2.6
self.assertTrue(isinstance(r, Vector2D),
"Vector2D * c did not return a Vector2D.")
self.assertEqual(r.x, -2.6 * -1.4, "Vector2D * c failed [X].")
self.assertEqual(r.y, -2.6 * 0.20, "Vector2D * c failed [Y].")
def test_not_equal(self):
"""Inequality operator."""
self.assertFalse(
Vector2D(1, 2) != Vector2D(1, 2),
"Inequality operator returned true for equal vectors.")
self.assertTrue(
Vector2D(5, 2) != Vector2D(1, 2),
"Inequality operator returned false for a vector with non-equal x components."
)
self.assertTrue(
Vector2D(1, 5) != Vector2D(1, 2),
"Inequality operator returned false for a vector with non-equal y components."
)
def test_indexing(self):
"""Getting/setting components by indexing."""
v = Vector2D(2.5, 6.7)
v[0] = 1.0
v[1] = 2.0
# check getting/setting via valid indexes
self.assertEqual(v[0], 1.0, "Indexing failed [X].")
self.assertEqual(v[1], 2.0, "Indexing failed [Y].")
# check invalid indexes
with self.assertRaises(
IndexError,
msg="Invalid positive index did not raise IndexError."):
r = v[3]
with self.assertRaises(
IndexError,
msg="Invalid negative index did not raise IndexError."):
r = v[-1]
def test_initialise_invalid(self):
"""Initialisation with an invalid type should raise a TypeError."""
with self.assertRaises(TypeError, msg="Initialised with a string."):
Vector2D("spoon")
def test_initialise_indexable(self):
"""Initialisation with an indexable object."""
v = Vector2D(1.0, 2.0)
self.assertEqual(v.x, 1.0, "Initialisation with indexable failed [X].")
self.assertEqual(v.y, 2.0, "Initialisation with indexable failed [Y].")
def test_initialise_default(self):
"""Default initialisation, unit vector pointing along x-axis."""
v = Vector2D()
self.assertEqual(v.x, 1.0, "Default initialisation is not (1,0) [X].")
self.assertEqual(v.y, 0.0, "Default initialisation is not (0,0) [Y].")
def test_negate(self):
"""Negate operator."""
r = -Vector2D(2.5, 6.7)
self.assertEqual(r.x, -2.5, "Negation failed [X].")
self.assertEqual(r.y, -6.7, "Negation failed [Y].")
