text formatting in columns with hash?

[Anonymous Monk]

I have a text file in the form:

a b c
0 0 d
0 1 d
0 1 d
0 2 d
0 2 d
1 0 d
1 0 d
1 1 d
1 1 d
1 2 d
1 2 d

And want to get it into this form:

a b c    a b c    
0 0 d    1 0 d
0 1 d    1 0 d
0 1 d    1 1 d
0 2 d    1 2 d
0 2 d    1 2 d

I thought it would be easy to just load it into a hash and then be able to reprint it to a different file but it is not working since I can't figure out how to start back up at the top of a new column. This is what I have printing into one column:

foreach my $va (sort {$a <=> $b} keys %myhash) {
           foreach my $vb (sort {$a <=> $b} keys %{ $myhash{$va} }) {
                   my $vc = $myhash{$va}{$vb};
                print OUTFILE "$va\t$vb\t$vc\n";
            }
        }
}

I would appreciate any ideas for doing this effectivly.

[toolic]

This works if you have an even number of lines after the header, as your output does (your input has an odd number for some reason):

use warnings;
use strict;

my @lines = <DATA>;
chomp @lines;
my $head = shift @lines;

print "$head  $head\n";
my $count = @lines / 2;
for my $i (0 .. $count-1) {
    print "$lines[$i]  $lines[$i+$count]\n";
}


__DATA__
a b c
0 0 d
0 1 d
0 1 d
0 2 d
0 2 d
1 0 d
1 0 d
1 1 d
1 2 d
1 2 d

[BillKSmith]

The requirements seem a bit more complicated. In the output, only the 'a' value is different between the two columns. The string which does not fit that pattern is skipped.

UPDATE:  My description of the output is wrong!  I cannot figure out t
+he
real requirement.

[Loops]

I'm late to the party here, but thought i'd post what i was playing around with anyway...

#!/usr/bin/perl -w
use 5.012;

# Read in the header
my $hdr = <DATA>;
chomp $hdr;

my @lines;
my $line = 0;
my $column = -1;
my $previous_a = '';

while (<DATA>) {
        chomp;
        my ($a,$b,$c) = split;
        if ($a ne $previous_a) {
                $lines[0][++$column] = $hdr;
                $line = 1;
                $previous_a = $a;
        }
        $lines[$line++][$column] = $_;
}

$,="\t";
say map {defined($_) ? $_ : ''} (@$_) for (@lines);

__DATA__
a b c
0 0 d
0 1 d
0 1 d
0 2 d
0 2 d
1 0 d
1 0 d
1 1 d
1 1 d
1 2 d
1 2 d 
2 0 d
2 0 d
1 0 d
1 0 d
1 1 d
1 1 d
1 2 d
1 2 d

Produces:

a b c   a b c   a b c   a b c
0 0 d   1 0 d   2 0 d   1 0 d
0 1 d   1 0 d   2 0 d   1 0 d
0 1 d   1 1 d           1 1 d
0 2 d   1 1 d           1 1 d
0 2 d   1 2 d           1 2 d
        1 2 d           1 2 d

[Anonymous Monk]

Thanks so much everyone for all your help! I don't know if the output is going to be even or odd I just know that when the first column changes I wanted to start a new set of columns. The above code looks really good.

[poj]

Fill an array, use the value in col a as the column number and reset rows back to 0 when it changes

#!perl
use strict;
my @matrix=();
my $row = 0;
my $prev_a;
while (<DATA>){
  chomp;
  my ($col_a,undef) = split(' ',$_,2);
  $row = 0 if ($col_a != $prev_a);
  $matrix[$row][$col_a] = $_;
  $prev_a = $col_a;
  ++$row;
}

for my $ar_row (@matrix){
  print join "   ",@$ar_row,"\n"
}

__DATA__
0 0 d
0 1 d
0 1 d
0 2 d
0 2 d
1 0 d
1 0 d
1 1 d
1 2 d
1 2 d

poj

[2teez]

Hi,
..I thought it would be easy to just load it into a hash and then be able to reprint it to a different file but it is not working since I can't figure out how to start back up at the top of a new column...

You could do this:

use warnings;
use strict;
use Data::Dumper;

my $title =<DATA>;
my %hash;

while(<DATA>){
 chomp;
 my $val = substr $_,0,1;
   push @{$hash{$val}},$_;
}

print Dumper \%hash;

__DATA__
a b c
0 0 d
0 1 d
0 1 d
0 2 d
0 2 d
1 0 d
1 0 d
1 1 d
1 1 d
1 2 d
1 2 d

which produces this..

$VAR1 = {
          '1' => [
                   '1 0 d
',
                   '1 0 d
',
                   '1 1 d
',
                   '1 1 d
',
                   '1 2 d
',
                   '1 2 d '
                 ],
          '0' => [
                   '0 0 d
',
                   '0 1 d
',
                   '0 1 d
',
                   '0 2 d
',
                   '0 2 d
'
                 ]
        };

UPDATE...
You now have the hash you wanted, and since you have the title, in variable "$title", you can use it anytime you want.
Though the printing out you desire is left for OP... :)
Hope this helps.