NAME
    Math::BaseCnv - fast functions to CoNVert between number Bases

VERSION
    This documentation refers to version 1.4.75N0H5e of Math::BaseCnv, which
    was released on Wed May 23 00:17:05:40 2007.

SYNOPSIS
      use Math::BaseCnv;

      # CoNVert     63 from base-10 (decimal) to base- 2 (binary )
      $binary_63  = cnv(     63, 10,  2 );
      # CoNVert 111111 from base- 2 (binary ) to base-16 (hex    )
      $hex_63     = cnv( 111111,  2, 16 );
      # CoNVert     3F from base-16 (hex    ) to base-10 (decimal)
      $decimal_63 = cnv(   '3F', 16, 10 );
      print "63 dec->bin $binary_63 bin->hex $hex_63 hex->dec $decimal_63\n";

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
    <Ken@Forum.Swarthmore.Edu> fine Math::BaseCalc module.

PURPOSE
    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 arbitrary number base that is
    represented as characters. High-bit ASCII has proven somewhat
    problemmatic but at least BaseCnv can simply && realiably convert
    between any possible base between 2 && 64 (or 85). I'm happy with it &&
    employ b64() in places I probably shouldn't now =).

USAGE
  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() && b64sort() && 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.

  b64sort(@b64s)
    A way to sort b64 strings as though they were decimal numbers.

  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']
      'm64' => ['A'..'Z', 'a'..'z', '0'..'9', '+', '/'] # MIME::Base64
      'b64' => ['0'..'9', 'A'..'Z', 'a'..'z', '.', '_'] 
      'b85' => ['0'..'9', 'A'..'Z', 'a'..'z', '!', '#', # RFC 1924 for
                '$', '%', '&', '(', ')', '*', '+', '-', #   IPv6 addrs
                ';', '<', '=', '>', '?', '@', '^', '_', #   like in
                '`', '{', '|', '}', '~'               ] # Math::Base85

    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 (e.g., 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.

  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 &&
    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
    (i.e., 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.

2DO
    - better error checking
    - handle fractional parts? umm but I like using '.' as a b64 char so ','
    comma or some other separator?
    - What else does BaseCnv need?

CHANGES
    Revision history for Perl extension Math::BaseCnv:

    - 1.4.75N0H5e Wed May 23 00:17:05:40 2007
      * added b85 for IPv6, gen'd META.yml, rm'd BuildPL for now, up'd minor
      ver

    - 1.2.68J9uJQ Sat Aug 19 09:56:19:26 2006
      * added b64sort() && put pod at bottom

    - 1.2.59M7mRX Thu Sep 22 07:48:27:33 2005
      * testing Make as primary and BuildPL backup (needing rename for dot)

    - 1.2.59IBlgw Sun Sep 18 11:47:42:58 2005
      * testing just using Module::Build instead of MakeMaker

      * fixed test 12 which was failing on AMD64

      * added Build.PL to pkg

    - 1.2.54HK3pB Sun Apr 17 20:03:51:11 2005
      * removed 128 digit-set since some hi-bit chars cause probs on Win32

      * made bin/cnv only executable to go in EXE_FILES

      * made Math::BaseCalc a link in pod && updated License

    - 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

    - 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 (&& 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 && run:

      `perl Makefile.PL; make; make test; make install`

LICENSE
    Most source code should be Free! Code I have lawful authority over is &&
    shall be! Copyright: (c) 2003-2007, 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.

AUTHOR
    Pip Stuart <Pip@CPAN.Org>

