Finding range of a numpy array elements

I think np.ptp might do what you want:

http://docs.scipy.org/doc/numpy/reference/generated/numpy.ptp.html

r = np.ptp(a,axis=1)

where r is your range array.

Try this:

def range_of_vals(x, axis=0):
    return np.max(x, axis=axis) - np.min(x, axis=axis)