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.)
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