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