I assume from your example there are a known number of files (say 3), each with one line of comma-separated items (the same number in each).

Here is a simple way to get the given lines into @data (not tested). It's a lot like the one by Ovid but simpler because I don't have to sort file names. 

use strict;

sub split_file_line {
   my $file = shift;
   open(IN, "<".$file) || die "cannot open $file: $!";
   my @items = split /,/,chomp($_ = <IN>);
   close IN;
   return \@items;
}
   
my @data = ();
my @files = qw(header_data.dat);
my $nfiles = 3;
for (my $i = 1; $i <= $nfiles; $i++) {
   push @files,"daily_data${i}.dat";
}

foreach my $file (@files) {
  push @data, split_file_line($file);
}

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In reply to Re: Graphing basics.. by tall_man
in thread Graphing basics.. by Anonymous Monk

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