Base85(3pm) User Contributed Perl Documentation Base85(3pm)NAME
Math::Base85 - Perl extension for base 85 numbers, as referenced by RFC 1924
SYNOPSIS
use Math::Base85;
$bigint = from_base85($number);
$b85str = to_base85($bigint);
DESCRIPTION
RFC 1924 describes a compact, fixed-size representation of IPv6 addresses which uses a base 85 number system. This module handles some of
the uglier details of it.
The base 85 numbers (from 0 to 84) are as follows:
0..9 A..Z a..z ! # $ % & ( ) * + - ; < = > ? @ ^ _ ` { | } ~
At the moment, there's not much in this module. But it should be sufficient for the purposes of RFC 1924.
This module has a variable called $Math::Base85::base85_digits, which is a string containing the digits of the base 85 alphabet from lowest(0) to highest (~), in that order.
Additionally, the following two functions are defined for general use. (They will be exported upon request.)
from_base85
Parameters
A string composed of valid base 85 digits.
Returns
A "Math::BigInt" object representing the number.
to_base85
Parameters
A "Math::BigInt" object.
Returns
A string of base 85 digits representing the number.
AUTHOR
Tony Monroe <tmonroe+perl@nog.net>
SEE ALSO perl(1).
perl v5.12.4 2002-08-06 Base85(3pm)
Check Out this Related Man Page
bigrat(3pm) Perl Programmers Reference Guide bigrat(3pm)NAME
bigrat - Transparent BigNumber/BigRationale support for Perl
SYNOPSIS
use bigrat;
$x = 2 + 4.5,"
"; # BigFloat 6.5
print 1/3 + 1/4,"
"; # produces 7/12
DESCRIPTION
All operators (inlcuding basic math operations) are overloaded. Integer and floating-point constants are created as proper BigInts or
BigFloats, respectively.
Other than bignum, this module upgrades to Math::BigRat, meaning that instead of 2.5 you will get 2+1/2 as output.
MODULES USED
"bigrat" is just a thin wrapper around various modules of the Math::BigInt family. Think of it as the head of the family, who runs the
shop, and orders the others to do the work.
The following modules are currently used by bignum:
Math::BigInt::Lite (for speed, and only if it is loadable)
Math::BigInt
Math::BigFloat
Math::BigRat
MATH LIBRARY
Math with the numbers is done (by default) by a module called Math::BigInt::Calc. This is equivalent to saying:
use bigrat lib => 'Calc';
You can change this by using:
use bigrat lib => 'BitVect';
The following would first try to find Math::BigInt::Foo, then Math::BigInt::Bar, and when this also fails, revert to Math::BigInt::Calc:
use bigrat lib => 'Foo,Math::BigInt::Bar';
Please see respective module documentation for further details.
SIGN
The sign is either '+', '-', 'NaN', '+inf' or '-inf' and stored seperately.
A sign of 'NaN' is used to represent the result when input arguments are not numbers or as a result of 0/0. '+inf' and '-inf' represent
plus respectively minus infinity. You will get '+inf' when dividing a positive number by 0, and '-inf' when dividing any negative number by
0.
METHODS
Since all numbers are not objects, you can use all functions that are part of the BigInt or BigFloat API. It is wise to use only the bxxx()
notation, and not the fxxx() notation, though. This makes you independed on the fact that the underlying object might morph into a differ-
ent class than BigFloat.
EXAMPLES
perl -Mbigrat -le 'print sqrt(33)'
perl -Mbigrat -le 'print 2*255'
perl -Mbigrat -le 'print 4.5+2*255'
perl -Mbigrat -le 'print 3/7 + 5/7 + 8/3'
perl -Mbigrat -le 'print 12->is_odd()';
LICENSE
This program is free software; you may redistribute it and/or modify it under the same terms as Perl itself.
SEE ALSO
Especially bignum.
Math::BigFloat, Math::BigInt, Math::BigRat and Math::Big as well as Math::BigInt::BitVect, Math::BigInt::Pari and Math::BigInt::GMP.
AUTHORS
(C) by Tels <http://bloodgate.com/> in early 2002.
perl v5.8.0 2002-06-01 bigrat(3pm)