I have a problem grouping an array similar to SQL's GROUP BY. I need to group them by the first column. Arrays before and after: 
before: 

1 0
1 1
2 0
3 1 
4 3
4 6
------
after: 

1 0-1
2 0
3 1
4 3-6

[download]
Any ideas? Thanks.

In reply to Group 2d array by Anonymous Monk

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