NAME

Set::Infinite - Perl extension for Sets of intervals

SYNOPSIS

  use Set::Infinite;

  $a = Set::Infinite->new(1,2);
  print $a->union(5,6);

DESCRIPTION

Set::Infinite is a Set Theory module for infinite sets.

It works on strings, reals or integers. You can provide your own objects or let it make them for you using the `type'.

It works very well on dates, providing schedule checks (intersections) and unions.

EXPORT

None by default.

USAGE

        $a = Set::Infinite->new();
        $a = Set::Infinite->new(1);
        $a = Set::Infinite->new(1,2);
        $a = Set::Infinite->new($b);
        $a = Set::Infinite->new([1], [1,2], [$b]);

Mode functions:

        $a->real;

        $a->integer;

Logic functions:

        $logic = $a->intersects($b);

        $logic = $a->contains($b);

        $logic = $a->is_null;

Sets functions:

        $i = $a->union($b);     

        $i = $a->intersection($b);

        $i = $a->complement;
        $i = $a->complement($b);

        $i = $a->span;   

                result is INTERVAL, (min .. max)

        $a->add($b);   

                This is a short for:

                $a = $a->union($b);

Scalar functions:

        $i = $a->min;

        $i = $a->max;

        $i = $a->size;  

Perl functions:

        @b = sort @a;

        print $a;

Global functions:

        separators(@i)

                chooses the interval separators. 

                default are [ ] ( ) '..' ','.

        null($i)                

                chooses 'null' name. default is 'null'

        infinite($i)

                chooses 'infinite' name. default is 'inf'

        infinite

                returns an 'infinite' number.

        minus_infinite

                returns '-infinite' number.

        null

                returns 'null'.

        quantize($i)

                returns a tied reference to an array of sets.
                Each array have size $i.
                In some cases, one or more array members may be empty.

                Example: 

                        $a = Set::Infinite->new([1,3]);
                        print join (" ", $a->quantize(1) );

                Gives: 

                        [1..2) [2..3) [3..4)

        type($i)

                chooses an object data type. 

                default is none (a normal perl SCALAR).

                examples: 

                type('Math::BigFloat');
                type('Math::BigInt');
                type('Set::Infinite::Date');
                        See notes on Set::Infinite::Date below.

        tolerance(0)    defaults to real sets (default)
        tolerance(1)    defaults to integer sets

        real                    defaults to real sets (default)

        integer                 defaults to integer sets

Internal functions:

        $a->cleanup;

Notes on Set::Infinite::Date

Set::Infinite::Date is a Date "plugin" for sets.

It is invoked by:

        type('Set::Infinite::Date');

It requires HTTP:Date and Time::Local

It changes quantize function behaviour to accept time units:

        $a = Set::Infinite->new('2001-05-02', '2001-05-13');
        print "Weeks in $a: ", join (" ", $a->quantize('weeks', 1) );

        $a = Set::Infinite->new('09:30', '10:35');
        print "Quarters of hour in $a: ", join (" ", $a->quantize('minutes', 15) );

Units can be years, months, days, weeks, hours, minutes, or seconds.

max and min functions will show in date/time format, unless they are used with `0 + '.

CAVEATS

        $a = Set::Infinite->new(10,1);
                Will be interpreted as [1..10]

        $a = Set::Infinite->new(1,2,3,4);
                Will be interpreted as [1..2],[3..4] instead of [1,2,3,4].
                You probably want ->new([1],[2],[3],[4]) instead,
                or maybe ->new(1,4) 

        $a = Set::Infinite->new(1..3);
                Will be interpreted as [1..2],3 instead of [1,2,3].
                You probably want ->new(1,3) instead.

AUTHOR

        Flavio Soibelmann Glock <fglock@pucrs.br>

cpanm Set::Infinite

perl -MCPAN -e shell
install Set::Infinite