Petrovich declines Russian names

Do you often have to deal with declining usernames in Russian? When sending letters, when displaying pages and mentions, when generating advertisements? Most likely, you have to dodge and write all the messages in the nominative case - Ivanov Petr Sergeevich .

It is not always convenient, not always beautiful, not always appropriate. The Russian language is endowed with a rich morphology, which somewhat complicates its automatic processing. Everyone knows that anthroponyms , as nouns rely on, obey all the rules of word formation.

To solve this problem when using Ruby, there is Petrovich , a convenient lightweight library for automagical declination of Russian names, surnames and patronymic names.
')

The essence

The Petrovich algorithm is based on the manual derivation rule base. It will be very easy for an application programmer to work with the library: the input is a word in canonical form , the output is the word of the requested kind and case.

Using

The basic syntax is simple enough to understand.

petrovich = Petrovich.new(:male) petrovich.lastname('', :dative) # =>  petrovich.firstname('', :dative) # =>  petrovich.middlename('', :dative) # =>  

As you can see, there are two parameters that describe the behavior of the analyzer: the floor is passed to the constructor of the Petrovich class, the case is passed to the second parameter of the declination method.

First, the gender of the name. Petrovich considers three options:

• male gender :male ;
• female, :female ;
• “Androgynous” gender :androgynous , in which the shape of the last name does not depend on the gender of the person. For example, Prokopenko .

Secondly, the required case. Valid cases that change the word are described below in the table.

Death case	Characterizing question	Designation
Genitive	Whom? What?	genitive
Dative	To whom? What	dative
Accusative	Whom? What?	accusative
Instrumental	By whom? Than?	instrumental
Prepositional	About whom? About what?	prepositional

It is possible to mix the module Petrovich::Extension into any class. This is especially useful when using ActiveRecord and similar ORM.

 class User < ActiveRecord::Base include Petrovich::Extension petrovich :firstname => :my_firstname, :middlename => :my_middlename, :lastname => :my_lastname, :gender => :my_gender def my_firstname '' end def my_middlename '' end def my_lastname '--' end #     ,    #    .      , #        . def my_gender :male # :male, :female  :androgynous end end 

Using the petrovich method, methods representing the last name, first name and patronymic are indicated. In this example, it is indicated that the method my_firstname represents the name, the method my_lastname represents the last name, the method my_middlename represents the middle name. Nothing prevents the module from being mixed into a regular class; everything will work just as well. Methods with the cases described in the table will be added to the target class.

 user = User.new user.my_firstname # =>  user.my_firstname_genitive # =>  user.my_middlename_genitive # =>  user.my_lastname_genitive # => -- 

Some features of Russian spelling are taken into account quite well.

Accuracy rating

For the sake of decency, an assessment was made of the accuracy of the declension of words. As a reference, a list of surnames and their forms was taken from the AOT morphological dictionary . Accuracy was evaluated based on processing 88,314 examples using the formula

,

where case is a case, gender is a gender, V _{case, gender} is the number of correct inflection for the specified case and gender, N _{case, gender} is the total number of examples for the specified case and gender.

At the time of this writing, an average accuracy of 99.6614% is observed based on processing 88,314 examples. Details are given in the table below. This information may be useful when using Petrovich in combat.

Gender / Case	Genitive	Dative	Accusative	Instrumental	Prepositional
Male	99.7137%	99.7386%	99.7635%	97.9858%	99.7261%
Female	99.9102%	99.9401%	99.9701%	99.4636%	99.9401%

Requisites

The repository on GitHub is located at petrovich / petrovich-ruby . The library is distributed under the MIT License. The authors of the library are Andrei Kozlov ( Bonch ) and Dmitry Ustalov ( dustalov ).

To install Petrovich and use it in your own applications, just run gem install petrovich or add the appropriate line in the Gemfile .

Web interface

It's nice that Andrei Sitnik ( Iskin ) from Evil Martians made a cool interface that allows you to play with Petrovich directly from the browser.



Currently, the interface is available at http://petrovich.nlpub.ru/ .

Porting

It would be great if developers working with other programming languages ​​would have ported this library to their languages. We are happy to answer any questions about Petrovich. In general, you can start porting with our rule base .

Thank you for reading to the end!

The illustrations with Petrovich belong to Andrei Bilzho, the author of comics about Petrovich .