3159mLT - Math::BaseCnv.pm created by Pip@CPAN.Org to convert between
arbitrary number bases. I'm totally addicted to bass!
NAME
Math::BaseCnv - fast functions to convert between number bases
VERSION
This documentation refers to version 1.2.45UC8fo of
Math::BaseCnv, which was released on Sun May 30 12:08:41:50 2004.
SYNOPSIS
use Math::BaseCnv;
# Convert 63 from base-10 (decimal) to base-2 (binary)
$binary_63 = cnv( 63, 10, 2 );
DESCRIPTION
BaseCnv provides a few simple functions for converting between
arbitrary number bases. It is as fast as I currently know how to
make it (of course relying only on the lovely Perl). If you
would rather utilize an object syntax for number-base conversion,
please see Ken Williams's fine
Math::BaseCalc module.
2DO
- better error checking
- handle fractional parts? umm but I like using '.' as a b64 char
so ',' comma as separator?
- What else does BaseCnv need?
WHY?
The reason I created BaseCnv was that I needed a simple way to
convert quickly between the 3 number bases I use most (10, 16, and
64). It turned out that it was trivial to handle any number base
that could be represented as characters. High-bit ASCII proved
somewhat problemmatic but at least BaseCnv can convert between any
possible base between 2 and 128 which is much more than I originally
needed. I'm quite happy with it and employ b64() too much now =).
I'm totally addicted to bass! Sometimes I intentionally misspell
'base' as 'bass' because I'm a dork who likes bass in my face.
USAGE
cnv($numb[,$from[,$tobs]])
CoNVert the number contained in $numb from its current number base
($from) into the result number base ($tobs).
B
If $numb only contains valid decimal (base 10) digits, it will be
converted to hexadecimal (base 16).
If $numb only contains valid hexadecimal (base 16) digits or begins
with '0x', it will be it will be converted to decimal (base 10).
B
cnv() assumes that $numb is already in decimal format and uses $from
as the $tobs.
B
The normal (and most clear) usage of cnv() is to provide all three
parameters where $numb is converted from $from base to $tobs.
cnv() is the only function that is exported from a normal
'use Math::BaseCnv;' command. The other functions below can be imported
to local namespaces explicitly or with the following tags:
:all - every function described here
:hex - only dec() and hex()
:b64 - only b10() and b64() and cnv()
:dig - only dig() and diginit()
:sfc - only summ(), fact(), and choo()
b10($b64n)
A shortcut to convert the number given as a parameter
($b64n) from base 64 to decimal (base 10).
b64($b10n)
A shortcut to convert the number given as a parameter
($b10n) from decimal (base 10) to base 64.
dec($b16n)
A shortcut to convert the number given as a parameter
($b16n) from hexadecimal (base 16) to decimal (base 10).
hex($b10n)
A shortcut to convert the number given as a parameter
($b10n) from decimal (base 10) to hexadecimal (base 16).
Please read the [NOTES] regarding hex().
dig(\@newd)
Assign the new digit character list to be used in
place of the default one. dig() can also alternately accept a
string name matching one of the following predefined digit sets:
'bin' => ['0', '1']
'oct' => ['0'..'7']
'dec' => ['0'..'9']
'hex' => ['0'..'9', 'a'..'f']
'HEX' => ['0'..'9', 'A'..'F']
'b62' => ['0'..'9', 'a'..'z', 'A'..'Z']
'64' => ['A'..'Z', 'a'..'z', '0'..'9', '+', '/'] # MIME::Base64
'b64' => ['0'..'9', 'A'..'Z', 'a'..'z', '.', '_']
'128' => ['0'..'9', 'A'..'Z', 'a'..'z', '.', '_'... higher chars
If no \@newd list or digit set name is provided as a parameter,
dig() returns the current character list. It's fine to have many
more characters in your current digit set than will be used with
your conversions (eg. using dig('128') works fine for any cnv()
call with $from and $tobs params less than or equal to 128).
An example of a \@newd parameter for a specified alternate digit
set for base 9 conversions is:
dig( [ qw( n a c h o z y u m ) ] );
diginit()
Resets the used digit list to the initial default order
of the predefined digit set: '128'. This is simply a shortcut for
calling dig('128') for reinitialization purposes.
summ($numb)
A simple function to calculate a memoized summation of $numb down to 1.
fact($numb)
A simple function to calculate a memoized factorial of $numb.
choo($ennn, $emmm)
A simple function to calculate a memoized function of $ennn choose $emmm.
NOTES
The Perl builtin hex() function takes a hex string as a parameter and
returns the decimal value (FromBase = 16, ToBase = 10) but this
notation seems counter-intuitive to me since a simple reading of the
code suggests that a hex() function will turn your parameter into
hexadecimal (ie. It sounds like Perl's hex() will hexify your parameter
but it does not.) so I've decided (maybe foolishly) to invert the
notation for my similar functions since it makes more sense to me this
way and will be easier to remember (I've had to lookup hex() in the
Camel book many times already which was part of the impetus for this
module... as well as the gut reaction that sprintf() is not a proper
natural inverse function for hex()).
This means that my b64() function takes a decimal number as a
parameter and returns the base64 equivalent (FromBase = 10, ToBase =
64) and my b10() function takes a base64 number (string) and returns
the decimal value (FromBase = 64, ToBase = 10). My hex() function
overloads Perl's builtin version with this opposite behavior so my
dec() function behaves like Perl's normal hex() function. I know
it's confusing and maybe bad form of me to do this but I like it
so much better this way that I'd rather go against the grain.
Please think of my dec() and hex() functions as meaning decify and
hexify. Also the pronunciation of dec() is 'dess' (!'deck' which
would be the inverse of 'ink' which -- and ++ already do so well).
After reading the informative Perl module etiquette guidelines, I now
appreciate the need to export as little as is necessary by default.
So to be responsible, I have limited BaseCnv exporting to only
cnv() under normal circumstances. Please specify the other
functions you'd like to import into your namespace or use the tags
described above in the cnv() section like:
'use Math::BaseCnv qw(:all !:hex);'
Error checking is minimal.
This module does not handle fractional number inputs because I like
using the dot (.) character as a standard base64 digit since it
makes for clean filenames.
summ(), fact(), and choo() are general Math function utilities which
are unrelated to number-base conversion but I didn't feel like making
another separate module just for them so they snuck in here.
I hope you find Math::BaseCnv useful. Please feel free to e-mail
me any suggestions or coding tips or notes of appreciation
("app-ree-see-ay-shun"). Thank you. TTFN.
CHANGES
Revision history for Perl extension Math::BaseCnv:
- 1.2.45UC8fo Sun May 30 12:08:41:50 2004
* tidied POD && upped minor version number since CPAN can't read PTVR
- 1.0.44E9ljP Wed Apr 14 09:47:45:25 2004
* added test for div-by-zero error in choo()
* added summ()
- 1.0.446EIbS Tue Apr 6 14:18:37:28 2004
* snuck in fact() && choo()
- 1.0.42REDir Fri Feb 27 14:13:44:53 2004
* changed test.pl to hopefully pass MSWin32-x86-multi-thread
- 1.0.428LV46 Sun Feb 8 21:31:04:06 2004
* broke apart CHANGES to descend chronologically
* made dec() auto uppercase param since dec(a) was returning 36 instead of 10
- 1.0.41M4GMP Thu Jan 22 04:16:22:25 2004
* put cnv in bin/ as EXE_FILES
- 1.0.418BEPc Thu Jan 8 11:14:25:38 2004
* testing new e auto-gen MANIFEST(.SKIP)?
- 1.0.3CNH37s Tue Dec 23 17:03:07:54 2003
* updated POD
- 1.0.3CG3dIx Tue Dec 16 03:39:18:59 2003
* normalized base spelling and other eccentricities
- 1.0.3CD1Vdd Sat Dec 13 01:31:39:39 2003
* added ABSTRACT section to WriteMakeFile()
* changed synopsis example
* updated all POD indenting
- 1.0.3CCA5Mi Fri Dec 12 10:05:22:44 2003
* removed indenting from POD NAME field
- 1.0.3CB7M43 Thu Dec 11 07:22:04:03 2003
* updated package to coincide with Time::Fields release
- 1.0.39B36Lv Thu Sep 11 03:06:21:57 2003
* synchronized POD with README documentation using new e utility
* templatized package compilation
* fixed boundary bugs
- 1.0.37SLNGN Mon Jul 28 21:23:16:23 2003
* first version (and my first Perl module... yay!) put on CPAN
- 1.0.37JKj3w Sat Jul 19 20:45:03:58 2003
* reworked interface from shell utility to package
- 1.0.3159mLT Sun Jan 5 09:48:21:29 2003
* original version
INSTALL
Please run:
`perl -MCPAN -e "install Math::BaseCnv"`
or uncompress the package and run the standard:
`perl Makefile.PL; make; make test; make install`
LICENSE
Most source code should be Free!
Code I have lawful authority over is and shall be!
Copyright: (c) 2003, Pip Stuart. All rights reserved.
Copyleft : I license this software under the GNU General Public
License (version 2). Please consult the Free Software Foundation
(http://www.fsf.org) for important information about your freedom.
AUTHOR
Pip Stuart