barak.interp.CubicSpline¶

class barak.interp.CubicSpline(x, y, firstderiv=None, lastderiv=None, nochecks=False)[source]¶

Class to generate a cubic spline through a set of points.

After initialisation, an instance can be called with an array of values xp, and will return the cubic-spline interpolated values yp = f(xp).

The spline can be reset to use a new first and last derivative while still using the same initial points by calling the set_d2() method.

If you want to calculate a new spline using a different set of x and y values, you’ll have to instantiate a new class.

The spline generation is based on the NR algorithms (but not their code.)

__init__(x, y, firstderiv=None, lastderiv=None, nochecks=False)[source]¶

Parameters :	x, y : arrays of floats, shape (N,) x and y = f(x). firstderiv : float (None) Derivative of f(x) at x[0] lastderiv : float (None) Derivative of f(x) at x[-1] nochecks : bool (False) If False, check the x array is sorted and unique. Set to True for increased speed.

Methods

__init__(x, y[, firstderiv, lastderiv, nochecks])	Parameters:
set_d2([firstderiv, lastderiv, verbose])	Calculates the second derivative of a cubic spline function y = f(x) for each value in array x.