colour.Extrapolator¶
-
class
colour.
Extrapolator
(interpolator=None, method='Linear', left=None, right=None, dtype=<class 'numpy.float64'>)[source]¶ Bases:
object
Extrapolates the 1-D function of given interpolator.
The
colour.Extrapolator
class acts as a wrapper around a given Colour or scipy interpolator class instance with compatible signature. Two extrapolation methods are available:Linear: Linearly extrapolates given points using the slope defined by the interpolator boundaries (xi[0], xi[1]) if x < xi[0] and (xi[-1], xi[-2]) if x > xi[-1].
Constant: Extrapolates given points by assigning the interpolator boundaries values xi[0] if x < xi[0] and xi[-1] if x > xi[-1].
Specifying the left and right arguments takes precedence on the chosen extrapolation method and will assign the respective left and right values to the given points.
- Parameters
-
__class__
()¶
Notes
The interpolator must define x and y attributes.
References
Examples
Extrapolating a single numeric variable:
>>> from colour.algebra import LinearInterpolator >>> x = np.array([3, 4, 5]) >>> y = np.array([1, 2, 3]) >>> interpolator = LinearInterpolator(x, y) >>> extrapolator = Extrapolator(interpolator) >>> extrapolator(1) -1.0
Extrapolating an array_like variable:
>>> extrapolator(np.array([6, 7 , 8])) array([ 4., 5., 6.])
Using the Constant extrapolation method:
>>> x = np.array([3, 4, 5]) >>> y = np.array([1, 2, 3]) >>> interpolator = LinearInterpolator(x, y) >>> extrapolator = Extrapolator(interpolator, method='Constant') >>> extrapolator(np.array([0.1, 0.2, 8, 9])) array([ 1., 1., 3., 3.])
Using defined left boundary and Constant extrapolation method:
>>> x = np.array([3, 4, 5]) >>> y = np.array([1, 2, 3]) >>> interpolator = LinearInterpolator(x, y) >>> extrapolator = Extrapolator(interpolator, method='Constant', left=0) >>> extrapolator(np.array([0.1, 0.2, 8, 9])) array([ 0., 0., 3., 3.])
-
property
interpolator
¶ Getter and setter property for the Colour or scipy interpolator class instance.
- Parameters
value (callable) – Value to set the Colour or scipy interpolator class instance with.
- Returns
Colour or scipy interpolator class instance.
- Return type
callable
-
property
left
¶ Getter and setter property for left value to return for x < xi[0].
- Parameters
value (numeric) – Left value to return for x < xi[0].
- Returns
Left value to return for x < xi[0].
- Return type
numeric
-
property
method
¶ Getter and setter property for the extrapolation method.
- Parameters
value (unicode) – Value to set the extrapolation method. with.
- Returns
Extrapolation method.
- Return type
unicode
-
property
right
¶ Getter and setter property for right value to return for x > xi[-1].
- Parameters
value (numeric) – Right value to return for x > xi[-1].
- Returns
Right value to return for x > xi[-1].
- Return type
numeric