mirror of https://github.com/NaN-tic/nanscan.git
60 lines
1.8 KiB
Python
60 lines
1.8 KiB
Python
# Copyright (C) 2008 by Albert Cervera i Areny
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# albert@nan-tic.com
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the
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# Free Software Foundation, Inc.,
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# 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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class Levenshtein:
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@staticmethod
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def levenshtein( text1, text2 ):
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d = []
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# Should use an array instead..
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for i in range(len(text1)):
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d.append( [] )
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for j in range(len(text2)):
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d[i].append(0)
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for i in range(len(text1)):
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d[i][0] = i
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for j in range(len(text2)):
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d[0][j] = j
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for i in range(len(text1)-1):
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for j in range(len(text2)-1):
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ip = i+1
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jp = j+1
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if text1[ip] == text2[jp]:
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cost = 0
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else:
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cost = 1
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d[ip][jp] = min(
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d[ip-1][jp] + 1, # deletion
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d[ip][jp-1] + 1, # insertion
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d[ip-1][jp-1] + cost # substitution
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)
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return d[len(text1)-1][len(text2)-1]
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if __name__ == '__main__':
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print Levenshtein.levenshtein( 'abc', 'abc' )
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print Levenshtein.levenshtein( 'abcabc', 'abc' )
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print Levenshtein.levenshtein( 'abcdef', 'abc' )
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print Levenshtein.levenshtein( 'abcdef', 'bcd' )
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print Levenshtein.levenshtein( 'bcdef', 'abc' )
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for x in range(10000):
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Levenshtein.levenshtein( 'text de la plantilla', 'text llarg que pot ser del document que tractem actualment' )
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