Special interpolations defined in terms of our custom Interpolation class.

# Documentation

Consider the signal to be piecewise constant, where the leading value is used for filling the interval [0,1).

cubic :: (C t, C t y) => T t ySource

Consider the signal to be piecewise cubic,
with smooth connections at the nodes.
It uses a cubic curve which has node values
x0 at 0 and x1 at 1 and derivatives
(x1-xm1)*2 and (x2-x0)*2, respectively.
You can see how it works
if you evaluate the expression for t=0 and t=1
as well as the derivative at these points.

piecewiseConstant :: C t y => T t ySource

piecewiseLinear :: C t y => T t ySource

piecewiseCubic :: (C t, C t y) => T t ySource