($ #: I.@,)2 2 $0 1 1 1
0 1
1 0
1 1
>Date: Sat, 31 May 2014 14:57:43 +0100
>From: Jon Hough <[email protected]>
>To: "[email protected]" <[email protected]>
>Subject: [Jprogramming] Getting index in 2+d array
>Message-ID: <[email protected]>
>Content-Type: text/plain; charset="iso-8859-1"
>
>Probably a very simple question. For a single dimension array I can do
>I. 1 0 1 1 1 0 0 0 1 0 1
>0 2 3 4 8 10
>to get the nonzero indices.
>But I am not sure how to do this for a larger dimension. i.e. get the
(i,j) or (i,j,k) index of nonzero elements.
>e.g. for this matrix:
> arr =. 3 3 $ 1 0 0 0 1 0 0 0 1
>I. doesn't work because it only gives me the ith value of the position
of the nonzero elements.
>Any help appreciated.
>Regards.
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