numpy - Compute divergence of vector field using python

Question

Is there a function that could be used for calculation of the divergence of the vectorial field? (in matlab) I would expect it exists in numpy/scipy but I can not find it using Google.

I need to calculate div[A * grad(F)], where

F = np.array([[1,2,3,4],[5,6,7,8]]) # (2D numpy ndarray)

A = np.array([[1,2,3,4],[1,2,3,4]]) # (2D numpy ndarray)

so grad(F) is a list of 2D ndarrays

I know I can calculate divergence like this but do not want to reinvent the wheel. (I would also expect something more optimized) Does anyone have suggestions?

Answer 1

Just a hint for everybody reading that:

the functions above do not compute the divergence of a vector field. they sum the derivatives of a scalar field A:

result = dA/dx + dA/dy

in contrast to a vector field (with three dimensional example):

result = sum dAi/dxi = dAx/dx + dAy/dy + dAz/dz

Vote down for all! It is mathematically simply wrong.

Cheers!