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Math::Random::MT::Auto::Range(3pm) User Contributed Perl Documentation Math::Random::MT::Auto::Range(3pm)

Math::Random::MT::Auto::Range - Range-valued PRNGs

    use strict;
    use warnings;
    use Math::Random::MT::Auto::Range;
    # Integer random number range
    my $die = Math::Random::MT::Auto::Range->new(LO => 1, HI => 6);
    my $roll = $die->rrand();
    # Floating-point random number range
    my $compass = Math::Random::MT::Auto::Range->new(LO => 0, HI => 360,
                                                     TYPE => 'DOUBLE');
    my $course = $compass->rrand();

This module creates range-valued pseudorandom number generators (PRNGs) that return random values between two specified limits.

While useful in itself, the primary purpose of this module is to provide an example of how to create subclasses of Math::Random::MT::Auto within Object::InsideOut's inside-out object model.

Add the following to the top of our application code:

    use strict;
    use warnings;
    use Math::Random::MT::Auto::Range;

This module is strictly OO, and does not export any functions or symbols.

Creates a new range-valued PRNG. 

    my $prng = Math::Random::MT::Auto::Range->new( %options );

Available options are:

'LOW' => $num
'HIGH' => $num
Sets the limits over which the values return by the PRNG will range. These arguments are mandatory, and "LOW" must not be equal to "HIGH".

If the "TYPE" for the PRNG is "INTEGER", then the range will be "LOW" to "HIGH" inclusive (i.e., [LOW, HIGH]). If "DOUBLE", then "LOW" inclusive to "HIGH" exclusive (i.e., [LOW, HIGH)).

"LO" and "HI" can be used as synonyms for "LOW" and "HIGH", respectively.

'TYPE' => 'INTEGER'
'TYPE' => 'DOUBLE'
Sets the type for the values returned from the PRNG. If "TYPE" is not specified, it will default to "INTEGER" if both "LOW" and "HIGH" are integers.

The options above are also supported using lowercase and mixed-case (e.g., 'low', 'hi', 'Type', etc.).

Additionally, objects created with this package can take any of the options supported by the Math::Random::MT::Auto class, namely, "STATE", "SEED" and "STATE".

$obj->new
Creates a new PRNG in the same manner as "Math::Random::MT::Auto::Range->new". 

    my $prng2 = $prng1->new( %options );

In addition to the methods describe below, the objects created by this package inherit all the object methods provided by the Math::Random::MT::Auto class, including the "-"clone()> method.

$obj->rrand
Returns a random number of the configured type within the configured range. 

    my $rand = $prng->rrand();

If the "TYPE" for the PRNG is "INTEGER", then the range will be "LOW" to "HIGH" inclusive (i.e., [LOW, HIGH]). If "DOUBLE", then "LOW" inclusive to "HIGH" exclusive (i.e., [LOW, HIGH)).

$obj->set_range_type
Sets the numeric type for the random numbers returned by the PRNG. 

    $prng->set_range_type('INTEGER');
      # or
    $prng->set_range_type('DOUBLE');
$obj->get_range_type
Returns the numeric type ('INTEGER' or 'DOUBLE') for the random numbers returned by the PRNG. 

    my $type = $prng->get_range_type();
$obj->set_range
Sets the limits for the PRNG's return value range. 

    $prng->set_range($lo, $hi);

$lo must not be equal to $hi.

$obj->get_range
Returns a list of the PRNG's range limits. 

    my ($lo, $hi) = $prng->get_range();

Capabilities provided by Object::InsideOut are supported by this modules. See "INSIDE-OUT OBJECTS" in Math::Random::MT::Auto for more information.

Object coercion is supported in the same manner as documented in See "Coercion" in Math::Random::MT::Auto except that the underlying random number method is "->rrand()".

  • Missing parameter: LOW
  • Missing parameter: HIGH

    The LOW and HIGH values for the range must be specified to ->new().

  • Arg to ->set_range_type() must be 'INTEGER' or 'DOUBLE'

    Self explanatory.

  • ->range() requires two numeric args

    Self explanatory.

  • Invalid arguments: LOW and HIGH are equal

    You cannot specify a range of zero width.

This module will reverse the range limits if they are specified in the wrong order (i.e., it makes sure that "LOW < HIGH").

Math::Random::MT::Auto

Object::InsideOut

Jerry D. Hedden, <jdhedden AT cpan DOT org>

Copyright 2005 - 2009 Jerry D. Hedden. All rights reserved.

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

2023-02-07 perl v5.36.0