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Math::BaseCnv - fast functions to convert between number bases |
cnv($numb[,$from[,$tobs]])b10($b64n)b64($b10n)dec($b16n)hex($b10n)dig(\@newd)diginit()summ($numb)fact($numb)
Math::BaseCnv - fast functions to convert between number bases
This documentation refers to version 1.2.59IBlgw of Math::BaseCnv, which was released on Sun Sep 18 11:47:42:58 2005.
use Math::BaseCnv;
# Convert 63 from base-10 (decimal) to base-2 (binary) $binary_63 = cnv( 63, 10, 2 );
BaseCnv provides a few simple functions for converting between arbitrary number bases. It is as fast as I currently know how to make it (of course relying only on the lovely Perl). If you would rather utilize an object syntax for number-base conversion, please see Ken Williams's <ken@forum.swarthmore.edu> fine the Math::BaseCalc manpage module.
The reason I created BaseCnv was that I needed a simple way to
convert quickly between the 3 number bases I use most (10, 16, &&
64). It turned out that it was trivial to handle any number base
that could be represented as characters. High-bit ASCII proved
somewhat problemmatic but at least BaseCnv can convert between any
possible base between 2 && 64. I'm happy with it && employ b64()
in places I probably shouldn't now =).
cnv($numb[,$from[,$tobs]])CoNVert the number contained in $numb from its current number base ($from) into the result number base ($tobs).
When only $numb is provided as a parameter:
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).
When only $numb && $from are provided as parameters:
cnv() assumes that $numb is already in decimal format && uses $from
as the $tobs.
When all three parameters are provided:
The normal (&& most clear) usage of cnv() is to provide all three
parameters where $numb is converted from $from base to $tobs.
cnv() is the only function that is exported from a normal
'use Math::BaseCnv;' command. The other functions below can be imported
to local namespaces explicitly or with the following tags:
:all - every function described here
:hex - only dec() && hex()
:b64 - only b10() && b64() && cnv()
:dig - only dig() && diginit()
:sfc - only summ(), fact(), && choo()
b10($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', '.', '_']
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('b64') works fine for any cnv()
call with $from && $tobs params less than or equal to 64).
An example of a \@newd parameter for a specified alternate digit set for base 9 conversions is:
dig( [ qw( n a c h o z y u m ) ] );
diginit()Resets the used digit list to the initial default order
of the predefined digit set: 'b64'. This is simply a shortcut for
calling dig('b64') for reinitialization purposes.
summ($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.
A simple function to calculate a memoized function of $ennn choose $emmm.
The Perl builtin hex() function takes a hex string as a parameter &&
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 && 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 && returns the base64 equivalent (FromBase = 10, ToBase =
64) && my b10() function takes a base64 number (string) && 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 && 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() && hex() functions as meaning decify &&
hexify. Also the pronunciation of dec() is 'dess' (!'deck' which
would be the inverse of 'ink' which -- && ++ 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(), && 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.
Revision history for Perl extension Math::BaseCnv:
* fixed test 12 which was failing on AMD64
* added Build.PL to pkg
* made bin/cnv only executable to go in EXE_FILES
* made Math::BaseCalc a link in pod && updated License
choo()
* added summ()
fact() && choo()
* made dec() auto uppercase param since dec(a) was returning 36 instead of 10
WriteMakeFile()
* changed synopsis example
* updated all POD indenting
* templatized package compilation
* fixed boundary bugs
Please run:
`perl -MCPAN -e "install Math::BaseCnv"`
or uncompress the package && run:
`perl Build.PL; perl Build; perl Build test; perl Build install`
Most source code should be Free! Code I have lawful authority over is && shall be! Copyright: (c) 2003-2005, Pip Stuart. Copyleft : This software is licensed under the GNU General Public License (version 2). Please consult the Free Software Foundation (http://FSF.Org) for important information about your freedom.
Pip Stuart <Pip@CPAN.Org>
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Math::BaseCnv - fast functions to convert between number bases |