?
Solved

calculating number combinations in perl

Posted on 2009-07-07
5
Medium Priority
?
204 Views
Last Modified: 2012-05-07
I have a small problem. I am working on a probability solution.

I have quasi-randomly generated data sets, from the value of 1 to 999. These values are the end result of another mathematical process.

The data comes out in groups of seven, eight and ten.

We have a mid range of 501-550.

If I could get help on the seven group problem, Im sure I could find my way with the other two groups when I can see the code structure.

I need to build a database (which could be a text file if it is big enough) of all possible value combinations, so out of the 50 numbers, from 501 to 550.

So the first possible combination would be
501,502,503,504,505,506,507

Then the next possible combination would be
501,502,503,504,505,506,508

And the combinations would tick up one at a time until
544,545,546,547,548,549,550, which would be the final one.

I expect about 10 million results.

I need each individual result output to a text file / word pad one line at a time, delineated by a comma.

Could you tell me perl code which would do this ?

Thankyou very much
0
Comment
Question by:Europa MacDonald
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
5 Comments
 
LVL 39

Expert Comment

by:Adam314
ID: 24799045

use Math::Combinatorics;
 
 
my $combin = Math::Combinatorics->new(count => 7, data => [501..550]);
 
while(my @combo = $combin->next_combination){
	print join(',', @combo)."\n";
}

Open in new window

0
 

Author Comment

by:Europa MacDonald
ID: 24799053
thankyou Adam

would this print out to a text file ?
0
 
LVL 13

Accepted Solution

by:
Carl Bohman earned 2000 total points
ID: 24799133
If you don't have Math::Combinatorics installed and can't install it for some reason, here's a code version.

For either my solution or Adam's, just redirect the output to a text file using the greater than symbol:
scriptname.pl > filename.txt
my $count = 3;
my $low = 501;
my $high = 550;
 
sub cmb
{
  my ($rem, $used, $text, $min) = @_;
  $rem--;
 
  for my $n ($min..($high - $rem))
  {
    next if $used->{$n};
    if ($rem)
    {
      $used->{$n} = 1;
      cmb($rem, $used, "$text$n,", $n + 1);
      $used->{$n} = 0;
    } else
    {
      print "$text$n\n"
    };
  }
}
 
my %h;
cmb($count, \%h, "", $low);

Open in new window

0
 

Author Comment

by:Europa MacDonald
ID: 24799168
thankyou

where would I put

scriptname.pl > filename.txt

?

0
 

Author Closing Comment

by:Europa MacDonald
ID: 31600854
worked out the file thing myself
thankyou very much
0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

In the distant past (last year) I hacked together a little toy that would allow a couple of Manager types to query, preview, and extract data from a number of MongoDB instances, to their tool of choice: Excel (http://dilbert.com/strips/comic/2007-08…
Checking the Alert Log in AWS RDS Oracle can be a pain through their user interface.  I made a script to download the Alert Log, look for errors, and email me the trace files.  In this article I'll describe what I did and share my script.
Explain concepts important to validation of email addresses with regular expressions. Applies to most languages/tools that uses regular expressions. Consider email address RFCs: Look at HTML5 form input element (with type=email) regex pattern: T…
Six Sigma Control Plans
Suggested Courses

765 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question