/ 
Set-Infinite-0.36_37
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/ Set::Infinite

NAME

Set::Infinite - Sets of intervals

SYNOPSIS

use Set::Infinite;

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

DESCRIPTION

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

It works on 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), unions, and infinite recurrences.

METHODS

is_too_complex

Sometimes a set might be too complex to print. It will happen when you ask for a quantization on a set bounded by -inf or inf.

copy

Makes a new object from the object's data.

Mode functions:

$a->real;

$a->integer;

Logic functions:

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

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

$logic = $a->is_null;

Set functions:

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

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

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

$i = $a->span;   

    result is INTERVAL, (min .. max)

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 ''

infinite($i)

    chooses 'infinite' name. default is 'inf'

infinite

    returns an 'infinite' number.

minus_infinite

    returns '-infinite' number.

null

    returns the 'null' object.

quantize( parameters )

    Makes equal-sized subsets.

    In array context: returns a tied reference to the subset list.
    In set context: returns an ordered set of equal-sized subsets.

    The quantization function is external to this module:
    Parameters may vary depending on implementation. 

    Positions for which a subset does not exist may show as null.

    Example: 

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

    Gives: 

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

select( parameters )

    Selects set members based on their ordered positions.
    Selection is more useful after quantization.

    In array context: returns a tied reference to the array of selected subsets.
    In set context: returns the set of selected subsets.

    Unselected subsets may show as null.

    The selection function is external to this module:
    Parameters may vary depending on implementation. 

        freq     - default=1
        by       - default=[0]
        count    - dafault=infinite

offset ( parameters )

    Offsets the subsets. Parameters: 

        value   - default=[0,0]
        mode    - default='offset'. Possible values are: 'offset', 'begin', 'end'.
        unit    - type of value. Can be 'days', 'weeks', 'hours', 'minutes', 'seconds'.

iterate ( sub { } )

    EXPERIMENTAL - may be removed in next release
    Iterates over a subroutine. 
    Returns the union of partial results.

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;

$a->backtrack($b);

$a->fixtype; 

$a->numeric;

Notes on Dates

See module Date::Set for up-to-date information on date-sets.

Set::Infinite::Date and Set::Infinite::ICal are Date "plugins" for sets.

use:

type('Set::Infinite::Date');  # 2001-05-02 10:00:00   
# or
type('Set::Infinite::ICal');  # 20010502T100000Z

Both require Time::Local. Set::Infinite::ICal requires Date::ICal.

They change quantize function behaviour to accept time units:

use Set::Infinite;
use Set::Infinite::Quantize_Date;
Set::Infinite->type('Set::Infinite::Date');
Set::Infinite::Date->date_format("year-month-day");

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

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

Quantize units can be years, months, days, weeks, hours, minutes, or seconds. To quantize the year to first-week-of-year until last-week-of-year, use 'weekyears':

->quantize( unit => weekyears, wkst => 1 )

'wkst' parameter is '1' for monday (default), '7' for sunday.

max and min functions will also show in date/time format.

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.

SEE ALSO

Date::Set

AUTHOR

Flavio Soibelmann Glock <fglock@pucrs.br>