y =. 3 5 ; 3 7 ; 3 8 ; 5 2 ; 5 6
>y
3 5
3 7
3 8
5 2
5 6
NB. you can form the boxed y from yours with
<"1 y
y { i. 10 10
35 37 38 52 56
NB. you would want something like
0 = y { tm
At 21:28 +0200 2008/01/03, Kairit Sirts wrote:
I have a 2 column matrix of indices: first column specifies the row index
and the second specifies the column index. There may be several records
pointing to one row. For example:
y
3 5
3 7
3 8
5 2
5 6
I have to check those specified locations in the target matrix to see if the
values there are 0 or not. How should I do that? The target matrix shape is
10000 500, which probably sets some limits to possible operations.
Kairit Sirts
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