Re: extract numbers from unformatted text strings

You can't count on knowing what the separator is going to be. It could be a string containing pretty much anything other than digits. Therefore:

use strict;
use warnings;

my $min = 1000000;
my $max = 0;
while (<DATA>) {
    m/(\d+)\D+(\d+)/;
    $min = $1 if $1 < $min;
    $max = $2 if $2 > $max;
}
print "$min-$max";

__DATA__
6-7
1 - 5
3 to 24
6 thru 9
2 through 11
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Comment on Re: extract numbers from unformatted text strings Download Code

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Re^2: extract numbers from unformatted text strings by fishbot_v2 (Chaplain) on May 23, 2005 at 17:54 UTC
Nice, but don't forget the first rule of a capturing `m//` - test for success before using `$1`... `while (<DATA>) { next unless m/(\d+)\D+(\d+)/; # or warn && next, or die $min = $1 if $1 < $min; $max = $2 if $2 > $max; }` [download] Also, rather than imposing an artificial limit on min (and max), what about addind a definedness check? `$min = $1 if ( ! defined( $min ) \|\| ( $1 < $min ) ); $max = $2 if ( ! defined( $max ) \|\| ( $1 > $max ) );` [download] I'll grant that the since this doesn't handle negative numbers (yet) anyway, max is likely fine the way it is.	[reply] [d/l] [select]

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Re^2: extract numbers from unformatted text strings
by fishbot_v2 (Chaplain) on May 23, 2005 at 17:54 UTC

Nice, but don't forget the first rule of a capturing m// - test for success before using $1...

while (<DATA>) {
    next unless m/(\d+)\D+(\d+)/;  # or warn && next, or die
    $min = $1 if $1 < $min;
    $max = $2 if $2 > $max;
}
[download]

Also, rather than imposing an artificial limit on min (and max), what about addind a definedness check?

    $min = $1 if ( ! defined( $min ) || ( $1 < $min ) );
    $max = $2 if ( ! defined( $max ) || ( $1 > $max ) );
[download]

I'll grant that the since this doesn't handle negative numbers (yet) anyway, max is likely fine the way it is.

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