In separate thread I needed to find the row and column indices of 1s in a
rectangular array.
tst=: _99&".;._2 (0 : 0)
0 0 0 1 0 0
0 0 0 0 0 0
1 0 0 0 0 0
0 0 0 1 0 0
0 0 0 0 0 0
1 0 0 0 0 0
)
indices tst
0 3
2 0
3 3
5 0
I came up with the following but feel I'm probably missing something (much)
simpler?
indices=: (1 , {:@$) *"1 [: (<. ,. 1&|) {:@$ %~ [: I. ,
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