Re: beginner - ordering tuples

If the file is like 7, 10\n, maybe

open(my $filehandle, '<', $filename)
  or die "error opening $filename: $!";

my @pairs = 
  sort { $$a[0] <=> $$b[1] }
  map { chomp; [ split /\s*,\s*/ ] }
  grep { /\S/ } # skip empty lines
  <$filehandle>;
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Re^2: beginner - ordering tuples by Anonymous Monk on Nov 13, 2010 at 01:09 UTC
I'm so much of a beginner I can't follow that. I will try and work it out but any help is appreciated.	[reply]
Re^3: beginner - ordering tuples by Anonymous Monk on Nov 13, 2010 at 01:13 UTC
the input file isn't in that format. i will have the values in 2 variables called $a and $b after i have parsed the line and i know $b will be higher than a for every row.	[reply]
Re^4: beginner - ordering tuples by Anonymous Monk on Nov 13, 2010 at 01:24 UTC
You might not want to use `$a` and `$b`, because those are built-in globals used by certain functions (eg sort). Assuming you're looping over each line: `my @pairs; while (<$filehandle>) { # or whatever loop construct # parse line and set $foo and $bar here # for example: chomp; my ($foo, $bar) = /(\d+)/g; # add to array push @pairs, [ $foo, $bar ]; } # sort array # NB: these are the special $a and $b, not yours @pairs = sort { $$a[0] <=> $$b[0] } @pairs;` [download]	[reply] [d/l] [select]