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SimpleVariable(3)     User Contributed Perl Documentation    SimpleVariable(3)

NAME
       Math::SimpleVariable - simple representation of mathematical variables

SYNOPSIS
	 use Math::SimpleVariable;

	 # Make	a variable
	 my $foo = new Math::SimpleVariable(name => 'foo', value => 0.3);

	 # Some	of the available accessors
	 # Note	that many are identical, but you might want to change
	 # their behaviour in derived variable classes...
	 my $name = $foo->name();	# yields 'foo'
	 print $foo->stringify(), "\n";	# prints 'foo'
	 my $id	= $foo->id();		# yields 'foo'
	 my $value = $foo->value();	# yields 0.3
	 print $foo->evaluate(), "\n";	# prints 0.3

	 # Make	a second variable
	 my $bar = $foo->clone();
	 $bar->{name} =	'bar';	    # changes the name (and as a consequence the id())
	 print $bar->value(), "\n"; # prints the same value, 0.3

DESCRIPTION
       Math::SimpleVariable is a simple	representation of mathematical
       variables, with an obligatory name and an optional value. This class on
       itself might not	seem very useful at first sight, but you might want to
       derive different	types of variables for some application. That way,
       objects of the derived variable class can be accessed interchangeably
       with the	here provided protocols.

       Math::SimpleVariable has	two data fields	- name and value - that	can be
       accessed	and modified as	if the variable	object is a hash. E.g.

	   $var->{name}	= 'foo';

       sets the	name of	the object $var	to 'foo', and

	   my $val = $var->{value};

       reads the value of the $var object into $val.

       In addition, the	following accessor methods are available for
       Math::SimpleVariable objects:

       $var->name()
	   Returns $var->{name}

       $var->id()
	   Returns $var->name()	for Math::SimpleVariable objects. The purpose
	   of id() is to provide some unique identifier	when using variables
	   in some higher level	concept, e.g. a	matrix representation of a set
	   of equations. Depending on your needs, you might want to change the
	   implementation of id() in derived classes.

       stringify()
	   Returns a printable representation of the variable. For
	   Math::SimpleVariable	objects, returns $var->name(). Again, you
	   might want to override this for derived classes.

       value()
	   Returns $var->{value}

       evaluate()
	   Returns a numerical evaluation of the variable. For
	   Math::SimpleVariable	objects, returns $var->value().	You might want
	   to override this behaviour in derived classes, athough I cannot
	   think of any	place where this might come in useful :-). evaluate()
	   is still there for reasons of orthogonality.

SEE ALSO
       perl(1).

VERSION
       This is CVS $Revision: 1.6 $ of Math::Simplevariable, last edited at
       $Date: 2001/10/31 12:38:39 $.

AUTHOR
       Wim Verhaegen <wimv@cpan.org>

COPYRIGHT
       Copyright (C) 2001 Wim Verhaegen. All rights reserved.  This program is
       free software; you may redistribute and/or modify it under the same
       terms as	Perl itself.

perl v5.24.1			  2017-07-03		     SimpleVariable(3)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | VERSION | AUTHOR | COPYRIGHT

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