m=: (10000 500 [EMAIL PROTECTED] 2) * 10000 500 [EMAIL PROTECTED] 0
y=: _2]\ 3 5 3 7 3 8 5 2 5 6
y
3 5
3 7
3 8
5 2
5 6
0 = (<"1 y){m
0 1 1 0 1
----- Original Message -----
From: Kairit Sirts <[EMAIL PROTECTED]>
Date: Thursday, January 3, 2008 11:29
Subject: [Jprogramming] selecting from matrix
To: 'Programming forum' <[email protected]>
> 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
> recordspointing 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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