Hello,

I have the following 2D array 
my @megaMotif = (
                  ["AGCT", "0", "370",  "1"],
                  ["AGGT", "3", "52",   "1"],
                  ["TGAA", "2", "233",  "0"],
                  ["AGAG", "0", "32",   "0"]
                );

[download]
The 2nd column may have numbers from 0 to 25. The third column will always be either 0 or 1.

I wish to sort this array by column 2nd as well as 4th!

This code sorts the array by 2nd column. 
for $mega( sort{ $a->[1] <=> $b->[1] } @megaMotif )
{
        print @$mega;        
        push (@megaMot, [@$mega]);
}

[download]
The output of this would be:
"AGCT" "0" "370" "1"
"AGAG" "0" "32" "0"
"TGAA" "2" "233" "0"
"AGGT" "3" "52" "1"

The first two rows are sorted by 2nd column...but not by the 4th.

But this is the desired output:
"AGAG" "0" "32" "0"
"AGCT" "0" "370" "1"
"TGAA" "2" "233" "0"
"AGGT" "3" "52" "1"

Note the first two rows of the desired output.

Ofcourse, this is just a portion of the entire 2000 row array. How may I do this efficiently?

Kindly help.

In reply to Sort a 2D array based on 2 columns by masala_curry

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