Hello Monks, I have written a simple script to read a tab-delimited file and write out a few selected columns to another tab-delimited file. Although my script is working OK, it seems to take more time than it should. It took 44 seconds to do its thing on a 4.22 MB file (2796 lines). Any insight would be greatly appreciated. Here's the code: 
while(<INFILE>)
{
    # get the current line and split into it's columns
    @Line = split /\s+/, $_;

    #print the selected columns to the output
    print OUTFILE join("\t",@Line[@ColumnNumbers]),"\n";
}

[download]
The @ColumnNumbers array has been defined previously, and would look something like: (1,10,32,69,200,291) UPDATE: The problem turned out not to be related to the code above. Thanks for the input though. Turns out I was running another algorithm every time through the loop that I thought I was only running the first time.

Retitled by davido from 'Why is this so slow?'.

In reply to Optimizing slow restructuring of delimited files by iKnowNothing

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