Yes it's possible. The special variable $. can be of great help, it keeps track of the line number of the filehandle you last read from. So you can do:
open IN, "<", $file or die "Can't open file $file: $!"; my %data; while(<IN>) { if($. == 1 || $. == 2) { my($number) = /([\d.]+)\s*$/; $data{$.} = $number; } }
If it doesn't match, it fills in undef for the data.

It's a bit silly for such small line numbers, but for larger numbers this approach begins to make sense.

I use a hash as a sparse array, it keeps a connection between the line number and the read data without wasting space for inbetween line numbers. Again, this makes most sense if your line numbers are much bigger than 1 or 2.

(update fixed error in code, thanks to davidrw for pointing that out.)


In reply to Re: Matching on a specific line of text by bart
in thread Matching on a specific line of text by kingdom

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