Fuzzy search

Ispell

When mnoGoSearch is used with ispell support all words are normalized. It allows finding different grammatical forms of the same words. During indexing all words are stored as in the database. During the search all forms of the given keyword are selected and are taken into account. E.g. search front-end will try to find the word "test" if "testing" or "tests" is given in search query.

Two types of ispell files

MnoGoSearch understands two types of ispell files: affixes and dictionaries. Ispell affixes file contains rules for words and has approximately the following format:


Flag V:
       E   > -E, IVE      # As in create> creative
      [^E] > IVE          # As in prevent > preventive
Flag *N:
       E   > -E, ION      # As in create > creation
       Y   > -Y, ICATION  # As in multiply > multiplication
     [^EY] > EN           # As in fall > fallen

Ispell dictionary file contains words themselves and has the following format:


wop/S
word/DGJMS
wordage/S
wordbook
wordily
wordless/P

Using Ispell

To make mnoGoSearch support ispell you must specify Affix and Spell commands in search.htm file. The format of commands:


Affix [lang] [charset] [ispell affixes file name]
Spell [lang] [charset] [ispell dictionary filename]

The first parameter of both commands is two letters language abbreviation. The second is ispell files charset. The third one is filename. File names are relative to mnoGoSearch /etc directory. Absolute paths can be also specified.

Note: Simultaneous loading of several languages is supported, e.g.:


Affix en iso-8859-1 en.aff
Spell en iso-8859-1 en.dict
Affix de iso-8859-1 de.aff
Spell de iso-8859-1 de.dict

Will load support for both English and German languages.

If you use searchd, add the same commands to searchd.conf.

When mnoGoSearch is used with ispell support it is recommended to use searchd, especially for several languages support. Otherwise the starting time of search.cgi increases.

Customizing dictionary

It is possible that several rare words are found in your site which are not in ispell dictionaries. You may create the list of such words in plain text file with the following format (one word per line):


rare.dict:
----------
webmaster
intranet
.......
www
http
---------

You may also use ispell flags in this file (for ispell flags refer to ISpell documentation). This will allow not writing the same word with different endings to the rare words file, for example "webmaster" and "webmasters". You may choose the word which has the same changing rules from existing ispell dictionary and just to copy flags from it. For example, English dictionary has this line:

postmaster/MS

So, webmaster with MS flags will be probably OK:

webmaster/MS

Then copy this file to /etc directory of mnoGoSearch and add this file by Spell command in ISpell tab of mnoGoSearch:

During next reindexing using of all documents new words will be considered as words with correct spelling. The only really incorrect words will remain.

Synonyms

Beginning from mnoGoSearch version 3.2 synonyms-based inexplicit search is supported.

Synonyms files are installed into etc/synonym subdirectory of mnoGoSearch installation.

To enable synonyms, add to search.htm search template commands like Synonym <filename>, e.g.:


Synonym synonym/english.syn
Synonym synonym/russian.syn

Filenames are relative to etc directory of mnoGoSearch installation or absolute if begin with /

If you use searchd, add the same commands to searchd.conf.

Please feel free to send us your own synonyms lists at . As an example you may take the english synonyms file. In the beginning of the list please specify the following two commands:


Language: en
Charset:  us-ascii