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NAME
    algorithm-networksort-chooser - Helper utility for
    Algorithm::Networksort

SYNOPSIS
    The "algorithm-networksort-chooser" script helps you find the best
    sorting network for your particular use-case.

        $ algorithm-networksort-chooser 9  ## find best sorting network for array size 9
        $ algorithm-networksort-chooser 9 --all  ## show all candiate networks
        $ algorithm-networksort-chooser 9 --algorithms=batcher,bitonic  ## only consider batcher and bitonic algos

        $ algorithm-networksort-chooser 9 --opt=comparators  ## optimise for comparators (default)
        $ algorithm-networksort-chooser 9 --opt=stages  ## optimise for stages

        $ algorithm-networksort-chooser 9 --median  ## best median network
        $ algorithm-networksort-chooser 9 --selection=4  ## also best median network
        $ algorithm-networksort-chooser 9 --selection=0,1,2  ## top-3 elements selection net

        $ algorithm-networksort-chooser 9 --validate  ## run 0-1 validation test
        $ algorithm-networksort-chooser 9 --show  ## show network as ASCII diagram
        $ algorithm-networksort-chooser 9 --raw  ## show network as raw comparators

DESCRIPTION
    This module uses Algorithm::Networksort to experiment with sorting
    networks.

    <Introduction To Sorting Networks>

    By default this script examines the output of all implemented algorithms
    and the currently best known special-cases, and chooses the one that
    best meets your specified criteria.

    This module allows you trim the sorting networks into median or
    selection networks.

    You can then choose to choose the optimal net based on comparators
    (total number of operations) or on stages (number of operations
    considering parallelism).

    Normally the output is something like this:

        $ algorithm-networksort-chooser --median 22
        Network size: 22
        Network type: Median network

        Optimisation criteria: stages

        Optimal network:
          Algorithm "best":
            Comparators: 86
            Stages: 12

    For the description of the various algorithms and best-known special
    cases, see Algorithm::Networksort's documentation and source code.

    In order to use this output in another program, there is a "--raw"
    switch. Its output is "eval"able perl and is valid JSON:

        $ algorithm-networksort-chooser --median 7 --raw
        [[0,4],[1,5],[2,6],[0,2],[1,3],[4,6],[2,4],[3,5],[0,1],[2,3],[4,5],[1,4],[3,6],[3,4]]

    Algorithm::Networksort's ASCII output can be seen with "--show":

        $ algorithm-networksort-chooser --median 7 --show
        Network size: 7
        Network type: Median network

        Optimisation criteria: comparators

        Optimal network:
          Algorithm "batcher":
            Comparators: 14
            Stages: 6

        o--^--------^-----^-----------------o
           |        |     |                  
        o--|--^-----|--^--v--------^--------o
           |  |     |  |           |         
        o--|--|--^--v--|--^-----^--|--------o
           |  |  |     |  |     |  |         
        o--|--|--|-----v--|--^--v--|--^--^--o
           |  |  |        |  |     |  |  |   
        o--v--|--|--^-----v--|--^--v--|--v--o
              |  |  |        |  |     |      
        o-----v--|--|--------v--v-----|-----o
                 |  |                 |      
        o--------v--v-----------------v-----o

    The "--all" switch shows all networks that were considered.

    Sometimes which algorithm or which best special-case network is
    surprising. For instance, selecting the top-3 elements in a size-9 array
    is best done by adapting Hibbard's algorithm, even though there is a
    special best (by comparators) network for size 9:

        $ algorithm-networksort-chooser 9 --selection=0,1,2 --all
        Network size: 9
        Network type: Selection network: 0,1,2

        Optimisation criteria: comparators

        Optimal network:
          Algorithm "hibbard":
            Comparators: 18
            Stages: 7

        Additional candidate networks:
          Algorithm "batcher":
            Comparators: 20
            Stages: 8
          Algorithm "bosenelson":
            Comparators: 22
            Stages: 10
          Algorithm "best":
            Comparators: 23
            Stages: 9
          Algorithm "bitonic":
            Comparators: 24
            Stages: 8
          Algorithm "bubble":
            Comparators: 36
            Stages: 15

FUTURE IDEAS
    Also optimise by average swaps

    Algorithm::Networksort::Validate::XS

SEE ALSO
    <Introduction To Sorting Networks>

    <Algorithm-Networksort-Chooser github repo>

    John Gamble's <Algorithm-Networksort github repo>

AUTHOR
    Doug Hoyte, "<doug@hcsw.org>"

COPYRIGHT & LICENSE
    Copyright 2013 Doug Hoyte.

    This module is licensed under the same terms as perl itself.