Dear Monks,

I have two arrays. I want to delete all elements in Array 2 that are not in Array 1. On top of that delete elements from Array 3 with the same index as those deleted in Array 2. This is very easy but the problem lies in speed. In R I can do it in seconds whereas if I do it in normal loop way in perl it will take ages. Is there a method to match R speed in this operation? Short example below;

@Array_1 = ("a1","a2","a3","a4","a5","a6");
@Array_2 = ("a1","b2","c3","a4","f5","a6");
@Array_3 = ("1","2","3","4","5","6");

output

@Array_2 = ("a1","a4","a6");
@Array_3 = ("1","4","6");

[download]

If I am doing operation on very large arrays is there a faster method than doing loops (I usually used foreach)? Thanks for sharing your wisdom.

In reply to Match speed of R in array procesing by Anonymous Monk

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