def test_project():
v = np.array([5.0, -3.0, 1.0])
onto = np.array([0, -1.0, 0])
expected_s = 3.0
expected_v = np.array([0, -3.0, 0])
np.testing.assert_array_almost_equal(vg.scalar_projection(v, onto=onto),
expected_s)
np.testing.assert_array_almost_equal(vg.project(v, onto=onto), expected_v)
with pytest.raises(
ValueError,
match=r"onto must be an array with shape \(3,\); got \(2, 3\)"):
vg.project(v, onto=np.array([vg.basis.x, vg.basis.x]))
def test_project_stacked_vs():
vs = np.array([[5.0, -3.0, 1.0], [1.0, 0, 1.0], [0.0, 1, 0.0],
[0.0, 0, 0.0]])
onto = np.array([0, -1.0, 0])
expected_s = np.array([3.0, 0.0, -1.0, 0])
expected_v = np.array([[0.0, -3.0, 0.0], [0.0, 0, 0.0], [0.0, 1.0, 0.0],
[0.0, 0, 0.0]])
np.testing.assert_array_almost_equal(vg.scalar_projection(vs, onto=onto),
expected_s)
np.testing.assert_array_almost_equal(vg.project(vs, onto=onto), expected_v)
def project_to_line(points, reference_points_of_lines, vectors_along_lines):
k = check_shape_any(points, (3, ), (-1, 3), name="points")
check_shape_any(
reference_points_of_lines,
(3, ),
(-1 if k is None else k, 3),
name="reference_points_of_lines",
)
vg.shape.check(locals(), "vectors_along_lines",
reference_points_of_lines.shape)
return reference_points_of_lines + vg.project(
points - reference_points_of_lines, onto=vectors_along_lines)
def project_point_to_line(points, reference_points_of_lines, vectors_along_lines):
"""
Project a point to a line, or pairwise project a stack of points to a
stack of lines.
"""
k = check_shape_any(points, (3,), (-1, 3), name="points")
check_shape_any(
reference_points_of_lines,
(3,),
(-1 if k is None else k, 3),
name="reference_points_of_lines",
)
vg.shape.check(locals(), "vectors_along_lines", reference_points_of_lines.shape)
return reference_points_of_lines + vg.project(
points - reference_points_of_lines, onto=vectors_along_lines
)
def oriented_along(self, along, reverse=False):
"""
Flip the polyline, if necessary, so that it points (approximately)
along the second vector rather than (approximately) opposite it.
"""
if self.is_closed:
raise ValueError("Can't reorient a closed polyline")
vg.shape.check(locals(), "along", (3,))
if self.num_v < 2:
return self
extent = self.v[-1] - self.v[0]
projected = vg.project(extent, onto=along)
if vg.scale_factor(projected, along) * (-1 if reverse else 1) < 0:
return self.copy().flip()
else:
return self
def aligned_with(self, vector):
"""
Flip the polyline if necessary, so it's aligned with the given
vector rather than against it. Works on open polylines and considers
only the two end vertices.
"""
if self.is_closed:
raise ValueError("Can't align a closed polyline")
vg.shape.check(locals(), "vector", (3, ))
if self.num_v < 2:
return self
extent = self.v[-1] - self.v[0]
projected = vg.project(extent, onto=vector)
if vg.scale_factor(projected, vector) < 0:
return self.flipped()
else:
return self
def test_project_error():
with pytest.raises(ValueError,
match="Not sure what to do with 3 dimensions"):
vg.project(np.array([[[5.0, -3.0, 1.0]]]), onto=np.array([0, -1.0, 0]))