Original content of parent
Hi,

I have a list of 2 variable $a $b $a can be from -180 up to 180 $b also can be from -180 up to 180 I want to create a 360 x 360 array and fill it with zeros then go throw the list and record the counts of the combination of $a and $b (i.e. every time I find a combination of 2 4 I will add +1 to the count)

For example a list of:

3 0
1 2
2 4
3 0
3 3
2 4


  0 1 2 3 4
0 0 0 0 2 0
1 0 0 0 0 0
2 0 1 0 0 0
3 0 0 0 1 0
4 0 0 2 0 0

[download]

Could you please help me? I don’t know how to start :s

Thx

I think you mean 361 x 361. Arrays must have non-negative indexes, so just store everything 180 indexes higher. 

$a[$row][$col]

[download]
becomes 
$a[$row + 180][$col + 180]

[download]

In reply to Re: 2 dimensional array by ikegami
in thread 2 dimensional array by topaz

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