Math::SymbolicX::NoSimplification - Turn off Math::Symbolic simplification

Math-SymbolicX-NoSimplification documentation Contained in the Math-SymbolicX-NoSimplification distribution.

Index

Code Index:

NAME

Top

Math::SymbolicX::NoSimplification - Turn off Math::Symbolic simplification

SYNOPSIS

Top

  use Math::SymbolicX::NoSimplification qw(:all);
  # ... code that uses Math::Symbolic ...
  # Won't use the builtin simplification routines.
  # ...
  do_simplify();
  # ... code that uses Math::Symbolic ...
  # Will use the builtin simplification routines.
  # ...
  dont_simplify();
  # ... you get the idea ...

DESCRIPTION

Top

This module offers facilities to turn off the builtin Math::Symbolic simplification routines and replace them with routines that just clone the objects. You may want to do this in cases where the simplification routines fail to simplify the Math::Symbolic trees and waste a lot of CPU time. (For example, calculating the first order Taylor polynomial of a moderately complex test function was sped up by 100% on my machine.)

A word of caution, however: If you turn off the simplification routines, some procedures may produce very, very large trees. One such procedure would be the consecutive application of many derivatives to a product without intermediate simplification. This would yield exponential growth of nodes. (And may, in fact, still do if you keep the simplification heuristics turned on because most expressions cannot be simplified significantly.)

USAGE

Just load the module to turn off simplification. To turn it back on, you can call Math::SymbolicX::NoSimplification-do_simplify()> and to turn it off again, you may call Math::SymbolicX::NoSimplification-do_simplify()>. Since the module's name is quite long, you may choose to import do_simplify() and/or dont_simplify() into your namespace using standard Exporter semantics. See below.

CLASS METHODS

do_simplify

Turn simplification back on.

dont_simplify

Turn simplification off.

EXPORT

None by default, but you may choose to import either the routines do_simplify() and/or dont_simplify() or both by using the :all exporter group. See also: Exporter

AUTHOR

Top

Steffen Mueller, <smueller@cpan.org>

Please send feedback, bug reports, and support requests to the Math::Symbolic support mailing list: math-symbolic-support at lists dot sourceforge dot net. Please consider letting us know how you use Math::Symbolic. Thank you.

If you're interested in helping with the development or extending the module's functionality, please contact the developers' mailing list: math-symbolic-develop at lists dot sourceforge dot net.

COPYRIGHT AND LICENSE

Top

Copyright (C) 2005-2006 Steffen Mueller

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

SEE ALSO

Top

New versions of this module can be found on http://steffen-mueller.net or CPAN.

Math::Symbolic,

Math-SymbolicX-NoSimplification documentation Contained in the Math-SymbolicX-NoSimplification distribution. 
package Math::SymbolicX::NoSimplification;

use 5.006;
use strict;
use warnings;

# We don't need exports
use Math::Symbolic qw();

# But we might export ourselves
require Exporter;
our @ISA = qw(Exporter);
our %EXPORT_TAGS = ( 'all' => [ qw(
	dont_simplify
	do_simplify
) ] );
our @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );
our @EXPORT = qw();

our $VERSION = '1.01';

# This is what we do instead of simplifying: Cloning
sub _Minimum_Simplification_Sub  {
	# Minimum simplification method clones.
	return $_[0]->new();
};

# This is where we save the simplification routines for
# later reinstallation using 'do_simplify()'
sub _Simplification_Sub_Cache {}
{
	# no warnings since we're redefining the simplify routine.
	# It is sufficient to redefine the one in ::Operator since that
	# is the only one that does anything but cloning.
	no warnings;
	*_Simplification_Sub_Cache = \&Math::Symbolic::Operator::simplify;
}

# A call to this will replace the simplify() routine in M::S::Operator with
# one that just clones (see above)
sub dont_simplify {
	no warnings;
	*Math::Symbolic::Operator::simplify =
		\&Math::SymbolicX::NoSimplification::_Minimum_Simplification_Sub;
}

# A call to this routine will undo all the damage dont_simplify() may have
# done by restoring the simplification routine in M::S::Operator from the
# backup in this module's &Simplification_Sub_Cache.
sub do_simplify {
	no warnings;
	*Math::Symbolic::Operator::simplify = \&Math::SymbolicX::NoSimplification::_Simplification_Sub_Cache;
}

# By default, if you load this module, we don't simplify.
dont_simplify();

1;
__END__