Need help for a loop with random permuted numbers and feed the permutated values to a perl code

Question

I have a well-written perl code (not authored by me), I want to use it for some analysis and need it to iterate over 1000 times with different set of input parameters. I will explain:

perl cmh-test.pl --input C1_E1_C2_E2_C3_E3_C4_E4_java.sync --output C1_E1_C2_E2_C3_E3_C4_E4_java.latest.cmh --min-count 20 --min-coverage 30 --max-coverage 400 --population 1-2,3-4,5-6,7-8 --remove-temp

I now want to run the same code 1000 times, but change the --population parameter every time such as where the first time it was 1-2,3-4,5-6,7-8, next time it becomes a random permutation of 1 to 8, such as 1-3,2-4,5-7,6-8 and so on. How do I do this?

Any help will be greatly appreciated.

Answer 1

As brian d foy suggests in the comments, see the answer posted by daxim on Reddit: https://www.reddit.com/r/perl/comments/jxneae/need_help_for_a_loop_with_random_permuted_numbers/

Below is an alternative solution, without using Algorithm::Combinatorics. Note that shuffle can generate repeating permutations. Also note that using a constant random seed as shown below generates the same permutation sequence every time the script is run. Remember to remove the srand statement if you do not care about reproducibility of the script across instances.

#!/usr/bin/env perl

use strict;
use warnings;
use feature qw( say );
use List::Util qw( shuffle );

# Use fixed seed to generate reproducible results across calls to this
# script. Omit this to use a default seed every instance:
srand 42; 

my @orig_pop = 1..8;

# Using strings to name output files: *_0001.cmh .. *_1000.cmh.
# Use numbers (1 .. 1000) if you want output files named: *_1.cmh .. *_1000.cmh.
for my $iter ( '0001' .. '1000' ) {
    my @pop = shuffle @orig_pop;
    # Using a hash to make array @pop into pairs:
    my %pop = @pop;
    my $pop = join ',', map { "$_-$pop{$_}" } grep { exists $pop{$_} } @pop;
    my $cmd = qq{perl cmh-test.pl } .
        qq{--input C1_E1_C2_E2_C3_E3_C4_E4_java.sync } .
        qq{--output C1_E1_C2_E2_C3_E3_C4_E4_java.latest_${iter}.cmh } .
        qq{--min-count 20 --min-coverage 30 --max-coverage 400 } .
        qq{--population $pop --remove-temp};
    say $cmd;
}