I've noticed an OpenCubicSpline class in the core module. I couldn't find an example in the code using grep. Could anybody answer this questions?
1) I understand that the values have to be evenly-spaced. Then, why asking for minrange and spacing ? Why not just use:
minrange = values[0]; spacing = values[1]-values[0]; ?
2) What is the minimum number of values required ? 4 ? 3) Do they need to be sorted ? 4) If I want to compute values out of range, should I use ClosedCubicSpline ?