# Raku-Lingua-Stem-Bulgarian ## Introduction This Raku package is for stemming Bulgarian words. It implements the BulStem algorithm presented in [[PN1](http://lml.bas.bg/~nakov/bulstem/)]. ------- ## Usage examples The `BulStem` function is used to find stems: ```perl6 use Lingua::Stem::Bulgarian; say BulStem('покълване') ``` ``` # покълв ``` `BulStem` also works with lists of words: ```perl6 say BulStem('Покълването на посевите се очаква с търпение, пиене и сланина.'.words) ``` ``` # (Покълване на посеви се очакв с търпени пи и слани) ``` The function `bg-word-stem` can be used as a synonym of `BulStem`. ------- ## Command Line Interface (CLI) The package provides the CLI function `BulStem`. Here is its usage message: ```shell > BulStem --help Usage: BulStem [--splitter=] [--format=] -- Finds stems of Bulgarian words in text. BulStem [--format=] [ ...] -- Finds stems of Bulgarian words. BulStem [--format=] -- Finds stems of Bulgarian words in (pipeline) input. Text to spilt and its words stemmed. --splitter= String to make a split regex with. [default: '\W+'] --format= Output format one of 'text', 'lines', or 'raku'. [default: 'text'] [ ...] Words to be stemmed. ``` Here are example shell commands of using the CLI function `BulStem`: ```shell > BulStem Какви Какв > BulStem --format=raku "Какви са стъблата на тези думи" # ["Какв", "с", "стъблат", "н", "тез", "дум"] > BulStem Какви са стъблата на тези думи # Какв с стъблат н тез дум ``` Here is a pipeline example using the CLI function `GetTokens` of the package ["Grammar::TokenProcessing"](https://github.com/antononcube/Raku-Grammar-TokenProcessing), [AAp1]: ```shell GetTokens ./RecommenderPhrases-template | BulStem --format=raku # ("colnames", "rownames", "агрегац", "агрегир", "ан", "аномал", "аномал", "близос", # "взем", "внуш", "глобал", "глобалн", "гъстот", "докаж", "доказателств", "доказателств", # "елемент", "етик", "заред", "изполва", "индексира", "истор", "консума", "латент", # "латентн", "локал", "локалн", "матриц", "матриц", "напречн", "нещ", "нещ", # "номализац", "нормализато", "нормализира", "обед", "обедин", "обработ", "обрат", # "обратн", "обясн", "обясн", "обясн", "повечет", "подход", "подход", "пр", "пр", # "препор", "препор", "препоръч", "препоръч", "препоръча", "препоръч", "препоръч", # "препоръчителк", "препоръчк", "препоръчк", "при", "проф", "размер", "разреденос", # "редиц", "свидетелств", "свидетелств", "свойств", "свойств", "семантич", "съсед", # "терм", "функци", "характеристи", "характеристи", "честот", "чре") ``` **Remark:** These kind of tokens (literals) transformations are used in the package ["DSL::Bulgarian"](https://github.com/antononcube/Raku-DSL-Bulgarian), [AAp2]. ------- ## Other implementations [C#](https://github.com/tbmihailov/bulstem-cs), [GATE plugin (Java)](https://gate.ac.uk/gate/plugins/Lang_Bulgarian/src/gate/bulstem/BulStemPR.java) [Java (JDK 1.4)](http://lml.bas.bg/~nakov/bulstem/Stemmer.java), [Perl (Original)](http://lml.bas.bg/~nakov/bulstem/apply_stem.pl), [Python2](https://github.com/peio/PyBulStem), [Python3](https://github.com/mhardalov/bulstem-py), [Ruby](https://github.com/tbmihailov/bulstem) ------- ## Implementation notes - The resource files are essential for the implementation of `BulStem`. - I had problems ingesting the stem-rules files in [PNp1] with my OS/IDE setup, so I used the files in [MHp1]. - The resource files are used to make the Bulgarian stemming rules. - The stemming rules `Hash` object is made at compile time. - There are 120765 stemming rules with frequencies (counts) ≥ 1. - By default rules with count ≥ 2 are loaded used. ------- ## TODO - [X] DONE Respect the word case in the returned result. - `BulStem('ТАБЛА')` should return `'ТАБЛ'`. - (Not `'табл'` as it currently does.) - [X] DONE CLI that can be inserted in UNIX pipelines. - [X] DONE (Re-)ingestion of stem rules with different min counts. - [ ] TODO Performance statistics. - [ ] TODO More detailed documentation. ------- ## References ### Articles [PN1] Preslav Nakov, ["BulStem: Design and evaluation of inflectional stemmer for Bulgarian"](http://lml.bas.bg/~nakov/bulstem/index.html), In Workshop on Balkan Language Resources and Tools (Balkan Conference in Informatics). ### Packages [AAp1] Anton Antonov, [Grammar::TokenProcessing Raku package](https://github.com/antononcube/Raku-Grammar-TokenProcessing), (2022), [GitHub/antononcube](https://github.com/antononcube). [AAp2] Anton Antonov, [DSL::Bulgarian Raku package](https://github.com/antononcube/Raku-DSL-Bulgarian), (2022), [GitHub/antononcube](https://github.com/antononcube). [MHp1] Momchil Hardalov, [bulstem-py Python package](https://github.com/mhardalov/bulstem-py), (2020), (Release: v0.3.3), [GitHub/mhardalov](https://github.com/mhardalov). [PNp1] Preslav Nakov, [BulStem: Inflectional Stemmer for Bulgarian](http://lml.bas.bg/~nakov/bulstem/index.html), (2002), http://lml.bas.bg/~nakov.