=head1 NAME Quantum::Superpositions::Lazy - Weighted QM-like superpositions with lazy evaluation =head1 SYNOPSIS use Quantum::Superpositions::Lazy; # superpos() accepts a list or an array reference my $position_1 = superpos(1 .. 10); my $position_2 = superpos(1 .. 10); # most standard perl operators are supported my $multiplication_plate = $position_1 * $position_2; # get something randomly my $random_outcome = $multiplication_plate->collapse; =head1 DESCRIPTION This module allows for creation of superpositions that contain a set of possible states. A superposition is an object that tries to behave as if it was in all of these states at once when used in regular numeric / string operations. Any operation that involves a superposition will yield a new superposition-like calculation object. Superpositions can be collapsed, which happens when they are stringified or manually upon calling the I method. During collapsing, a random element from all the possible outcomes is chosen and saved as a current persistent state of a superposition. For calculations created from superpositions, all the source superpositions are collapsed as well. Many parts of the module are lazy by nature - they are only calculated as late as possible, which is also how quantum physics work. Those lazily generated states are also persistent - once generated, they will be cached for later (re)use. The most prominent example of that would be the behavior of computations made on superpositions. Instead of generating all the outcomes right away, references to source superpositions and the type of operation are stored. They are only called once the computation is observed (collapsed). This is mostly where the quantum physics part of the module ends. The rest of the capabilities go beyond that and allow for calculations on uncollapsed superpositions. It's important to note that these calculations are extremely slow by their nature. Adding one of 1000 numbers to one of another 1000 numbers just to get one state randomly is very fast because of the optimizations made. Doing any kind of serious calculations on this volume of data (basically a million objects) is only valid for educational purposes, toy programs and other kinds of not very serious work. =head1 CAPABILITIES / FEATURES =head2 Superpositions and calculations =over 2 =item * quantum-like superpositions with weighted states, containing any data =item * persistent state after collapsing, manual state clearing =item * superposition objects can be used with most native Perl operators =item * calculation results are objects that reference the source objects =item * collapsing a calculation result also collapses the source superpositions =back =head2 Complete set of superposition states =over 2 =item * ability to get a complete set of superposition states, together with their calculated weights (the cartesian product) =item * exporting the states to ket notation =item * extracting statistical data from the superpositions, like the most probable outcome or weighted mean =item * obtaining the sources of each and every state, which is the exact set calculation parameters used to obtain it =back =head1 FUNCTIONS =head2 superpos superpos(@data) superpos([@data]) Always exported. Feeds its arguments to the L constructor. If the only argument is an array reference, it is passed as-is into the constructor, resulting with a state for every array ref element. Otherwise creates a reference out of the arguments and passes them instead. # Creates 0.5|1> + 0.5|2> superpos(1, 2); # Same thing, but with explicit weights superpos([1, 1], [1, 2]); # Caution: this does not create 1|2>, but 0.5|1> + 0.5|2> superpos([1, 2]); # Any data is OK superpos(qw(dont eat the fish)); =head2 any_state =head2 every_state =head2 one_state any_state BLOCK every_state BLOCK one_state BLOCK Changes the behavior of superposition logical operations inside the block to return true if any / every / one element matches the criteria. The default behavior is I. Returns the value returned by the BLOCK. my $pos = superpos(1, 2, 3); $pos == 1; # true any_state { $pos == 1 }; # true every_state { $pos == 1 }; # false one_state { $pos == 1 }; # true =head2 fetch_matches fetch_matches BLOCK Changes the behavior of superposition logical operations inside the block to return a new superposition of left-hand superposition states that match the criteria instead of returning a boolean. This can be used to get more data about the superposition rather than just an information if it matches the criteria at all. Returns the value returned by the BLOCK. my $pos = superpos(1, 2, 3); $pos == 2; # true fetch_matches { $pos == 2 }; # a superposition: 1|2> =head2 with_sources with_sources BLOCK Changes the behavior of superposition mathematical operations inside the block to also contain the sources of the calculations made. This can be helpful to determine how the value was calculated. This is disabled by default due to the amount of extra memory needed by the states that are created this way. Returns the value returned by the BLOCK. my $calc = superpos(2, 3) * superpos(1, 2); # these states will now be instances of Quantum::Superpositions::Lazy::ComputedState my $states = with_sources { $calc->states }; # and contain source and operation fields which will hold: # source - an array reference of array references in form [$val1, $val2, ... $valn] # operation - instance of Quantum::Superpositions::Lazy::Operation::ComputationalOp =head1 DEVELOPMENT AND CONTRIBUTIONS The module is mostly finished feature-wise, as puting any more features into it would make it bloated. However, I'm open to suggestions - if you have one, open an issue on Github or send me an email and we can talk it through. =head1 AUTHOR Bartosz Jarzyna, Ebrtastic.dev@gmail.comE =head1 COPYRIGHT AND LICENSE Copyright (C) 2020 by Bartosz Jarzyna This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.24.0 or, at your option, any later version of Perl 5 you may have available. =cut cut