colour.kernel_cardinal_spline

colour.kernel_cardinal_spline(x, a=0.5, b=0.0)[source]

Returns the cardinal spline kernel evaluated at given samples.

Notable cardinal spline \(a\) and \(b\) parameterizations:

  • Catmull-Rom: \((a=0.5, b=0)\)
  • Cubic B-Spline: \((a=0, b=1)\)
  • Mitchell-Netravalli: \((a=\cfrac{1}{3}, b=\cfrac{1}{3})\)
Parameters:
  • x (array_like) – Samples at which to evaluate the cardinal spline kernel.
  • a (int, optional) – \(a\) control parameter.
  • b (int, optional) – \(b\) control parameter.
Returns:

The cardinal spline kernel evaluated at given samples.

Return type:

ndarray

References

Examples

>>> kernel_cardinal_spline(np.linspace(0, 1, 10))  
array([ 1.        ,  0.9711934...,  0.8930041...,  0.7777777...,  0.6378600...,
        0.4855967...,  0.3333333...,  0.1934156...,  0.0781893...,  0.        ])