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Data-TableData-Pick-0.001
River stage one • 1 direct dependent • 1 total dependent
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/ Data::TableData::Pick

NAME

Data::TableData::Pick - Pick randomly one or more table rows, with some options

VERSION

This document describes version 0.001 of Data::TableData::Pick (from Perl distribution Data-TableData-Pick), released on 2022-05-20.

FUNCTIONS

pick_table_rows

Usage:

 pick_table_rows(%args) -> [$status_code, $reason, $payload, \%result_meta]

Pick randomly one or more table rows, with some options.

This function takes table, a table data (either aos, aoaos, aohos, or a Data::TableData::Object instance) and picks one or more random rows from it and return the rows in the form of of aoaos or aohos.

No duplicates are picked (i.e. no resampling a.k.a. sampling without replacement), but of course duplicate rows can still happen if the input table itself contain duplicate rows.

If the requested number of rows (n) exceed the number of rows of the table, only up to the number of rows of the table are returned.

Weighting option. You can specify the name of column that contains weight.

This function is not exported by default, but exportable.

Arguments ('*' denotes required arguments):

  • n => posint (default: 1)

    Number of rows to pick.

  • table* => any

    A table data (either aos, aoaos, aohos, or a Data::TableData::Object instance).

  • weight_column => str

    Specify column name that contains weight.

    If not specified, all rows will have the equal weight of 1.

    Weight must be a non-negative real number.

Returns an enveloped result (an array).

First element ($status_code) is an integer containing HTTP-like status code (200 means OK, 4xx caller error, 5xx function error). Second element ($reason) is a string containing error message, or something like "OK" if status is 200. Third element ($payload) is the actual result, but usually not present when enveloped result is an error response ($status_code is not 2xx). Fourth element (%result_meta) is called result metadata and is optional, a hash that contains extra information, much like how HTTP response headers provide additional metadata.

Return value: (any)

HOMEPAGE

Please visit the project's homepage at https://metacpan.org/release/Data-TableData-Pick.

SOURCE

Source repository is at https://github.com/perlancar/perl-Data-TableData-Pick.

SEE ALSO

Data::TableData::Object

Array::Sample::WeightedRandom

AUTHOR

perlancar <perlancar@cpan.org>

CONTRIBUTING

To contribute, you can send patches by email/via RT, or send pull requests on GitHub.

Most of the time, you don't need to build the distribution yourself. You can simply modify the code, then test via:

 % prove -l

If you want to build the distribution (e.g. to try to install it locally on your system), you can install Dist::Zilla, Dist::Zilla::PluginBundle::Author::PERLANCAR, and sometimes one or two other Dist::Zilla plugin and/or Pod::Weaver::Plugin. Any additional steps required beyond that are considered a bug and can be reported to me.

COPYRIGHT AND LICENSE

This software is copyright (c) 2022 by perlancar <perlancar@cpan.org>.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

BUGS

Please report any bugs or feature requests on the bugtracker website https://rt.cpan.org/Public/Dist/Display.html?Name=Data-TableData-Pick

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.