

 
Manual Reference Pages  ALGORITHM::INTERVAL2PREFIX (3)
.ds Aq ’
NAME
Algorithm::Interval2Prefix  Generate prefixes from intervals
CONTENTS
SYNOPSIS
use Algorithm::Interval2Prefix;
my @prefixes = interval2prefix(33400,33599);
print join(,, @prefixes); # prints "334,335"
my $regex = interval2regex(33400,33599);
if ($n =~ /$regex/) { ... }
DESCRIPTION
Taking an interval as input, this module will construct the smallest
set of prefixes, such that all numbers in the interval will match
exactly one of the prefixes, and no prefix will match a number not in
the interval.
E.g. all numbers in the interval 39967000 to 39980999 would be matched
by the following set of prefixes:
39967
39968
39969
3997
39980
This type of conversion is particularly useful when working with
telephony switching equipment, which usually determines call routing
based on number prefixes rather than ranges.
Note that the numbers in the interval must be of the same length
for the result to make sense.
The algorithm is much dependent on the number base, which defaults to
10. Other number bases can be specified explicitly.
An additional function is provided, that will generate a regular
expression string matching <B>onlyB> those numbers in the interval.
FUNCTIONS
interval2prefix LO,HI,BASE


interval2prefix LO,HI

Yields an array of prefixes, covering the interval LO to HI,
using number base BASE.
BASE is optional, and defaults to 10.

interval2regex LO,HI

Yields a regular expression string, which will match <B>onlyB> those
numbers in the interval.
This function assumes base 10.


EXPORT
Both interval2prefix() and interval2regex() are exported by default.
o

With interval2prefix(), the endpoints of the interval must be the
same length (same number of digits in the particular number base)
for the results to make any sense.

o

interval2regex() only does base 10.


Please report issues via CPAN RT:
http://rt.cpan.org/NoAuth/Bugs.html?Dist=AlgorithmInterval2Prefix
or by sending mail to
bugAlgorithmInterval2Prefix@rt.cpan.org
AUTHOR
Lars Thegler <lars@thegler.dk>
COPYRIGHT
Copyright (c) 2003 Lars Thegler. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
perl v5.20.3  INTERVAL2PREFIX (3)  20031202 
Visit the GSP FreeBSD Man Page Interface. Output converted with manServer 1.07. 