Hi everyone,

My question is the following:

I have values for a two-variable function y(x,a) on grid points. However, I want to do partial differentiation on another two-variable function z(x,y). What is the routines I should implement in the numerical recipes?

To have a concrete example, let's say y(0,0)=0, y(0,0.1)=3, y(0.1,0)=8, y(0.1,0.1)=5;

and I want to find dz/dx |y and dz/dy |x at (0.05,0.05)

dz/dx |y means partial_z over partial_x, fixing y.