refind.d2N

refind.d2N(N, wl, *args)

Second order derivative of the refractive index as function of wavelength using first-order finite difference.

Parameters:

• N (func) – (Complex) Refractive index as function of wavelength and possible arguments: N(wl, args).
• wl (array) – Wavelenth axis in um (can also be a single float).
• args (mixed) – Variable number of arguments to be provided to N.

Returns:

First order derivative of N with same shape as wl.