Get the position of the largest value in a multi-dimensional NumPy array

Question

How can I get get the position (indices) of the largest value in a multi-dimensional NumPy array?

Answer 1

The argmax() method should help.

Update

(After reading comment) I believe the argmax() method would work for multi dimensional arrays as well. The linked documentation gives an example of this:

>>> a = array([[10,50,30],[60,20,40]]) >>> maxindex = a.argmax() >>> maxindex 3 

Update 2

(Thanks to KennyTM's comment) You can use unravel_index(a.argmax(), a.shape) to get the index as a tuple:

>>> from numpy import unravel_index >>> unravel_index(a.argmax(), a.shape) (1, 0) 

Answer 2

(edit) I was referring to an old answer which had been deleted. And the accepted answer came after mine. I agree that argmax is better than my answer.

Wouldn't it be more readable/intuitive to do like this?

numpy.nonzero(a.max() == a) (array([1]), array([0])) 

Or,

numpy.argwhere(a.max() == a)