Numpy return array of index

Question

Probably this is a dummy question! But I simply can't find the answer!

For the following array np.arange(-3,3,1.2) I get this:

array([-3. , -1.8, -0.6,  0.6,  1.8])

and for this I want to get an index array like the following:

array([0, 1, 2, 3, 4])

Thanks in advance.

Surely you're not just looking for np.arange(5). So can you clarify the problem? — unutbu
– unutbu, Commented Apr 11, 2014 at 18:25
If you want to get the indices to that particular array (so that the lengths match), you could use np.arange(len(np.arange(-3, 3, 1.2))) — askewchan
– askewchan, Commented Apr 11, 2014 at 20:28

Saullo G. P. Castro · Accepted Answer · 2014-04-15 13:10:16Z

1

You can do:

a = np.array([-3. , -1.8, -0.6,  0.6,  1.8])
indices = np.arange(a.shape[0])

answered Apr 15, 2014 at 13:10

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