set::infinite::arithmetic(3pm) [debian man page]

Set::Infinite::Arithmetic(3pm)				User Contributed Perl Documentation			    Set::Infinite::Arithmetic(3pm)

       NAME

       Set::Infinite::Arithmetic - Scalar operations used by quantize() and offset()

       AUTHOR

       Flavio Soibelmann Glock - fglock@pucrs.br

       %_MODE hash of subs

	   $a->offset ( value => [1,2], mode => 'offset', unit => 'days' );

	   $a->offset ( value => [1,2, -5,-4], mode => 'offset', unit => 'days' );

       note: if mode = circle, then "-5" counts from end (like a Perl negative array index).

	   $a->offset ( value => [1,2], mode => 'offset', unit => 'days', strict => $a );

       option 'strict' will return intersection($a,offset). Default: none.

       %subs_offset2($object, $offset1, $offset2)

	   &{ $subs_offset2{$unit} } ($object, $offset1, $offset2);

       A hash of functions that return:

	   ($object+$offset1, $object+$offset2)

       in $unit context.

       Returned $object+$offset1, $object+$offset2 may be scalars or objects.

       %Offset_to_value($object, $offset)

       %Init_quantizer($object)

	   $Offset_to_value{$unit} ($object, $offset);

	   $Init_quantizer{$unit} ($object);

       Maps an 'offset value' to a 'value'

       A hash of functions that return ( int($object) + $offset ) in $unit context.

       Init_quantizer subroutines must be called before using subs_offset1 functions.

       int(object)+offset is a scalar.

       Offset_to_value is optimized for calling it multiple times on the same object, with different offsets. That's why there is a separate
       initialization subroutine.

       $self->{offset} is created on initialization. It is an index used by the memoization cache.

perl v5.10.0							    2008-06-21					    Set::Infinite::Arithmetic(3pm)

Set::Infinite::_recurrence(3pm) 			User Contributed Perl Documentation			   Set::Infinite::_recurrence(3pm)

NAME

       Set::Infinite::_recurrence - Extends Set::Infinite with recurrence functions

SYNOPSIS

	   $recurrence = $base_set->_recurrence ( &next, &previous );

DESCRIPTION

       This is an internal class used by the DateTime::Set module.  The API is subject to change.

       It provides all functionality provided by Set::Infinite, plus the ability to define recurrences with arbitrary objects, such as dates.

METHODS

       o   _recurrence ( &next, &previous )

	   Creates a recurrence set. The set is defined inside a 'base set'.

	      $recurrence = $base_set->_recurrence ( &next, &previous );

	   The recurrence functions take one argument, and return the 'next' or the 'previous' occurence.

	   Example: defines the set of all 'integer numbers':

	       use strict;

	       use Set::Infinite::_recurrence;
	       use POSIX qw(floor);

	       # define the recurrence span
	       my $forever = Set::Infinite::_recurrence->new(
		   Set::Infinite::_recurrence::NEG_INFINITY,
		   Set::Infinite::_recurrence::INFINITY
	       );

	       my $recurrence = $forever->_recurrence(
		   sub {   # next
			   floor( $_[0] + 1 )
		       },
		   sub {   # previous
			   my $tmp = floor( $_[0] );
			   $tmp < $_[0] ? $tmp : $_[0] - 1
		       },
	       );

	       print "sample recurrence ",
		     $recurrence->intersection( -5, 5 ), "
";
	       # sample recurrence -5,-4,-3,-2,-1,0,1,2,3,4,5

	       {
		   my $x = 234.567;
		   print "next occurence after $x = ",
			 $recurrence->{param}[0]->( $x ), "
";  # 235
		   print "previous occurence before $x = ",
			 $recurrence->{param}[2]->( $x ), "
";  # 234
	       }

	       {
		   my $x = 234;
		   print "next occurence after $x = ",
			 $recurrence->{param}[0]->( $x ), "
";  # 235
		   print "previous occurence before $x = ",
			 $recurrence->{param}[2]->( $x ), "
";  # 233
	       }

       o   is_forever

	   Returns true if the set is a single span, ranging from -Infinity to Infinity.

       o   _is_recurrence

	   Returns true if the set is an unbounded recurrence, ranging from -Infinity to Infinity.

CONSTANTS

       o   INFINITY

	   The "Infinity" value.

       o   NEG_INFINITY

	   The "-Infinity" value.

SUPPORT

       Support is offered through the "datetime@perl.org" mailing list.

       Please report bugs using rt.cpan.org

AUTHOR

       Flavio Soibelmann Glock <fglock@gmail.com>

       The recurrence generation algorithm is based on an idea from Dave Rolsky.

COPYRIGHT

       Copyright (c) 2003 Flavio Soibelmann Glock. All rights reserved.  This program is free software; you can distribute it and/or modify it
       under the same terms as Perl itself.

       The full text of the license can be found in the LICENSE file included with this module.

SEE ALSO

       Set::Infinite

       DateTime::Set

       For details on the Perl DateTime Suite project please see <http://datetime.perl.org>.

perl v5.12.4							    2011-08-22					   Set::Infinite::_recurrence(3pm)