Math-Telephony-ErlangB                  version                  1.0.0
====================================

The README is used to introduce the module and provide instructions on
how to install  the module, any machine dependencies  it may have (for
example C compilers and installed libraries) and any other information
that should be provided before the module is installed.

INSTALLATION

The easier installation method is using cpan and issue:

   install Math::Telephony::ErlangB

If you want to start from the gzipped archive, after extracting it 
you can type the following:

   perl Makefile.PL
   make
   make test
   make install

I recently started appreciating Module::Build, so you can also:

   perl Build.PL
   ./Build
   ./Build test
   ./Build install

It's up to you and to what you have installed.

TESTING

To run the tests just run

   make test
   # or, if using Module::Build
   ./Build test

as previously said. Version 0.02  includes a test suite based upon ITU
tables for Erlang B, available for free in variuos versions at

   http://www.itu.int/itudoc/itu-d/dept/psp/ssb/planitu/plandoc/erlangt.html

The adherence of module's formulas  to the table are still under test;
at  the moment,  to make  the tests  against these  tables pass  in my
machine I did the following:

* to test  the gos  function, I accepted  an absolute error  less than
1e-4.  Note that this  is not  acceptable at  the moment,  because lhe
lowest value for GoS in the table is 1e-5;

* to test the traffic function, I accepted an absolute error less than
3%, which again doesn't apply well for lower values of traffic;

* to test the servers function, I had to scale the traffic a bit. This
is necessary to  cope with roundoff and finite  machine precision, due
to  the  fact  that  the  number  of  servers  is  always  an  integer
number. This  is probably the  most acceptable function at  the moment
with respect the  table, but also note that it's  based upon the gos()
function.

The trembling adherence  to the table does not  surprise me very much;
the table  I'm using  actually should be  applied only to  the traffic
function based on its construction.  I also fear that ITU guys rounded
off a bit.

DEPENDENCIES

The de-facto standard module "version".

COPYRIGHT AND LICENCE

Copyright (C) 2005 by Flavio Poletti

This library is  free software; you can redistribute  it and/or modify
it under the same terms as  Perl itself, either Perl version 5.8.6 or,
at your option, any later version of Perl 5 you may have available.


