=begin RD

= Ruby/CERNLIB

a collection of Ruby extension libraries
to access various CERN Program Library


== about CERNLIB

The CERN Program Library is a collection of general purpose programs
maintained by CERN ASD group.
The Web site is ((<URL:http://wwwinfo.cern.ch/asd/>))


== about Ruby/CERNLIB

Ruby/CERNLIB is a collection of Ruby extension libraries to access CERNLIB.
Recent version of Ruby/CERNLIB is available from the Web site:
((<URL:http://www-ps.kek.jp/thitoshi/ruby/cern/>))
Ruby version 1.6.6 or later is required for Ruby/CERNLIB.

Currently, Ruby/CERNLIB contains following modules.
:Fortran
  Fortran-style file I/O
:HBook
  Histograms and N-tuples
:HIGZ
  Graphics
:HPlot
  Histogram plottings
:Mathlib
  Mathematical routines
:PHTools
  Phase-space calculation
:GEANT
  Detector description and simulation tools
:HBook2
  More Object-Oriented Histogram and N-tuple classes

Note that HBook2 module is very experimental,
so implementations and API's may be changed in future release.
GEANT module is also on early development stage
and only a few routines are implemented.


== Install

Configuration and build;
  % ruby extconf.rb
  % make
To install for system-wide use;
  % su
  # make install


== Methods

In HBook, HIGZ, HPlot, Mathlib, PHTools and GEANT modules,
each CERNLIB routine is defined as a module function
with a same name (all lower case).
Subroutine arguments for output are included in a returned value,
and you must give only input arguments to each method.
For example, to get a content of ch#(1, 2) of a 2-dimensional histogram ID#10,
  Real x, y
  Call HIJXY(10, 1, 2, x, y)
which can be written in Ruby/CERNLIB like
  x, y = CERN::HBook.hijxy(10, 1, 2)
Since Ruby's Array knows its length, you don't hove to specify a length
of array as an method argument.
For example, to draw a polyline with 4 points,
  Dimension x(4), y(4)
  Data x /1.4, 3.5, 4.5, 6.7/
  Data y /4.1, 5.3, 5.4, 7.6/
  Call IPL(4, x, y)
in Ruby/CERNLIB
  CERN::HIGZ.ipl [1.4, 3.5, 4.5, 6.7], [4.1, 5.3, 5.4, 7.6]
Each common block is defined as a Struct-like object
with an all-uppercase name.
In the PHTools module, for instance, the number of outgoing particles
can be set as
  CERN::PHTools::GENIN.np = 4
As For HBook2 module, see hbook2/hbook2.rd or hbook2/hbook2-ja.rd.


== License

Copyright (C) 1999 - 2003
TAKAHASHI Hitoshi <hitoshi.takahashi@kek.jp>

This program is free software; you can redistribute it and/or modify
it under the same license terms as Ruby.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

=end RD