NAME

Acme::CPANModules::PERLANCAR::Task::PickingRandomLinesFromFile - Picking random lines from a file

VERSION

This document describes version 0.001 of Acme::CPANModules::PERLANCAR::Task::PickingRandomLinesFromFile (from Perl distribution Acme-CPANModulesBundle-PERLANCAR), released on 2018-01-09.

DESCRIPTION

Picking random lines from a file.

INCLUDED MODULES

• File::Random

  The random_line() function from this module picks one or more random lines from a specified file. The whole content of the file need not be slurped into memory, but the routine requires a single-pass of reading all lines from the file. The algorithm is as described in perlfaq (See: perldoc -q "random line").

  If you pick more than one lines, then there might be duplicates.

• File::RandomLine - Recommended for large files

  This module gives you a choice of two algorithms. The first is similar to File::Random (the scan method), giving each line of the file equal weight. The second algorithm is more interesting: it works by random seeking the file, discarding the line fragment (a.k.a. searching forward for the next newline character), reading the next line, then repeating the process until the desired number of lines is reached. This means one doesn't have to read the whole file and the picking process is much faster than the scan method. It might be preferred for very large files.

  Note that due to the nature of the algorithm, lines are weighted by the number of characters. In other words, lines that have long lines immediately preceding them will have a greater probability of being picked. Depending on your use case or the line length variation of your file, this algorithm might or might not be acceptable to you.

• File::Random::Pick

  This module is an alternative to File::Random. It offers a random_line() routine that avoids duplication.

• App::PickRandomLines

  A CLI that allows you to use File::Random::Pick or File::RandomLine on the command-line.

HOMEPAGE

Please visit the project's homepage at https://metacpan.org/release/Acme-CPANModulesBundle-PERLANCAR.

SOURCE

Source repository is at https://github.com/perlancar/perl-Acme-CPANModulesBundle-PERLANCAR.

BUGS

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

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.

SEE ALSO

Acme::CPANModules - about the Acme::CPANModules namespace

cpanmodules - CLI tool to let you browse/view the lists

AUTHOR

perlancar <perlancar@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2018 by 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.