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    1/*  Part of SWI-Prolog
    2
    3    Author:        Jan Wielemaker
    4    E-mail:        J.Wielemaker@vu.nl
    5    WWW:           http://www.swi-prolog.org
    6    Copyright (c)  2011-2014, VU University Amsterdam
    7    All rights reserved.
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    9    Redistribution and use in source and binary forms, with or without
   10    modification, are permitted provided that the following conditions
   11    are met:
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   14       notice, this list of conditions and the following disclaimer.
   15
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   17       notice, this list of conditions and the following disclaimer in
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   21    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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   24    FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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   33*/
   34
   35:- module(isub,
   36          [ isub/4                      % +Text1, +Text2, +Normalize, -Distance
   37          ]).   38
   39
   40:- use_foreign_library(foreign(isub)).

isub: a string similarity measure

The library(isub) implements a similarity measure between strings, i.e., something similar to the Levenshtein distance. This method is based on the length of common substrings.

author
- Giorgos Stoilos
See also
-
A string metric for ontology alignment by Giorgos Stoilos, 2005. */
 isub(+Text1:text, +Text2:text, +Normalize:bool, -Similarity:float) is det
Similarity is a measure for the distance between Text1 and Text2. E.g.
?- isub('E56.Language', 'languange', true, D).
D = 0.711348.

If Normalize is true, isub/4 applies string normalization as implemented by the original authors: Text1 and Text2 are mapped to lowercase and the characters "._ " are removed. Lowercase mapping is done with the C-library function towlower(). In general, the required normalization is domain dependent and is better left to the caller. See e.g., unaccent_atom/2.

Arguments:
Text1- and Text2 are either an atom, string or a list of characters or character codes.
Similarity- is a float in the range [0.0..1.0], where 1.0 means most similar
   76:- multifile sandbox:safe_primitive/1.   77
   78sandbox:safe_primitive(isub:isub(_,_,_,_))