See below. I have added an extra pair of parantheses to make .9 optional... 

use warnings;
use strict;

my $f = 'chap 89.9';
if($f=~m/chap.( |[a-z])*(\d+)(\.(\d+))?/i)
{
        print "  $2 $4\n";
}

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In reply to Re: how to split full digit number? by hdb
in thread how to split full digit number? by virudinesh

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