def interpolated_matrix(CCT, CCT_1, CCT_2, M_1, M_2):
"""
Computes the matrix interpolated from :math:`CCT_1` and :math:`CCT_2`
correlated colour temperatures to respectively :math:`M_1` and :math:`M_2`
colour matrices using given correlated colour temperature :math:`CCT`
interpolation value.
Parameters
----------
CCT : numeric
Correlated colour temperature :math:`CCT`.
CCT_1 : numeric
Correlated colour temperature :math:`CCT_1`.
CCT_2 : numeric
Correlated colour temperature :math:`CCT_2`.
M_1 : array_like
:math:`M_1` colour matrix.
M_2 : array_like
:math:`M_2` colour matrix.
Returns
-------
ndarray
Interpolated colour matrix :math:`M_i`.
Notes
-----
- The computation is performed in mired (MIcro REciprocal Degree,
reciprocal megakelvin) :math:`MK^{-1}`.
Examples
--------
>>> CCT = 5000
>>> CCT_1 = 2850
>>> CCT_2 = 6500
>>> M_1 = np.array([
... [0.5309, -0.0229, -0.0336],
... [-0.6241, 1.3265, 0.3337],
... [-0.0817, 0.1215, 0.6664]])
>>> M_2 = np.array([
... [0.4716, 0.0603, -0.0830],
... [-0.7798, 1.5474, 0.2480],
... [-0.1496, 0.1937, 0.6651]])
>>> interpolated_matrix(CCT, CCT_1, CCT_2, M_1, M_2) # doctest: +ELLIPSIS
array([[ 0.4854908..., 0.0408106..., -0.0714282...],
[-0.7433278..., 1.4956549..., 0.2680749...],
[-0.1336946..., 0.1767874..., 0.6654045...]])
"""
if CCT <= CCT_1:
return M_1
elif CCT >= CCT_2:
return M_2
else:
return linear_conversion(1e6 / CCT, (1e6 / CCT_1, 1e6 / CCT_2),
tstack((M_1, M_2)))
def test_linear_conversion(self):
"""
Tests :func:`colour.utilities.array.linear_conversion` definition.
"""
np.testing.assert_almost_equal(
linear_conversion(np.linspace(0, 1, 10), np.array([0, 1]),
np.array([1, np.pi])),
np.array([
1.00000000, 1.23795474, 1.47590948, 1.71386422, 1.95181896,
2.18977370, 2.42772844, 2.66568318, 2.90363791, 3.14159265
]),
decimal=8)
def test_linear_conversion(self):
"""
Tests :func:`colour.utilities.array.linear_conversion` definition.
"""
np.testing.assert_almost_equal(
linear_conversion(
np.linspace(0, 1, 10), np.array([0, 1]), np.array([1, np.pi])),
np.array([
1.00000000, 1.23795474, 1.47590948, 1.71386422, 1.95181896,
2.18977370, 2.42772844, 2.66568318, 2.90363791, 3.14159265
]),
decimal=8)