#!/usr/bin/perl -w

# Split a tab-delimited text files into n files, repeating
# first column and shuffling columns.
# Julien Textoris

use strict;
use warnings;

open(IN, "$ARGV[0]");

my $n = $ARGV[1];

#Thanks to Q&A for this !
sub melange_fy {
	my $tab = shift;
	my $i;
	for($i = @$tab; --$i;) {
		my $j = int rand($i+1);
		next if ($i == $j);
		@$tableau[$i,$j] = @$tableau[$j,$i];
	}
}

my $perm =0 ;
my (@ind);

while ( my $ligne = <IN>) {
	$ligne =~ s/[\r\n]//g;
	
	my ($id,@elmt) = split(/\t/, $ligne);
	#make the permutation of tab indices only the first time
        unless($perm++) {
		@ind = (0..@elmt-1);
		melange_fy(\@ind);
	}

	
	my $w = int(scalar(@elmt)/$n+0.5);
	
	for(my $i = 0; $i < $n; $i++) {
		open (OUT, ">>$ARGV[0].$i");
		my $d = $i*$w;
		my($f);
		if($i == $n-1) {
			$f = scalar(@elmt)-1;
		}
			else {
			$f = $d+$w-1;
		}
		
		print OUT join("\t",$id,@elmt[@ind[$d..$f]])."\n";
		
		
		close(OUT);
		
	}
}

##</code><code>##

Genes	setA	setB	setC	setD	setE	setF	setG
g1	1	2	3	4	5	6	7
g2	1	2	3	4	5	6	7
g3	1	2	3	4	5	6	7