Need faster python code for calculating sample entropy

Question

This is the problem I have faced when I am writing python code for sample entropy.

map(max, abs(a[i]-a) ) is very slow.

Is there any other function perform better than map() ?

Where a is ndarray that looks like np.array([ [1,2,3,4,5],[2,3,4,5,6],[3,4,5,3,2] ])

What's `a` here? And is this Python 2.x or 3.x (`map()` is not the same in both)? — arshajii, Aug 27 '13 at 15:21
have you tried `import speed`? Seriously though, what does `a` look like and what is the required output? — inspectorG4dget, Aug 27 '13 at 15:21
is `a` a `numpy.ndarray`? (you can check this doing `type(a)`)... — Saullo G. P. Castro, Aug 27 '13 at 15:24

score 6 · Accepted Answer · answered Aug 27 '13 at 15:33

6

Use the vectorized max

>>> map(max, abs(a[2]-a) )
[3, 4, 0]
>>> np.abs(a[2] - a).max(axis=1)
array([3, 4, 0])

answered Aug 27 '13 at 15:33

Viktor Kerkez

1 Answers1