EVOLUTION-MANAGER

Edit File: lev.py

from __future__ import print_function from whoosh.compat import unichr, xrange from whoosh.automata.fsa import ANY, EPSILON, NFA, unull def levenshtein_automaton(term, k, prefix=0): nfa = NFA((0, 0)) if prefix: for i in xrange(prefix): c = term[i] nfa.add_transition((i, 0), c, (i + 1, 0)) for i in xrange(prefix, len(term)): c = term[i] for e in xrange(k + 1): # Correct character nfa.add_transition((i, e), c, (i + 1, e)) if e < k: # Deletion nfa.add_transition((i, e), ANY, (i, e + 1)) # Insertion nfa.add_transition((i, e), EPSILON, (i + 1, e + 1)) # Substitution nfa.add_transition((i, e), ANY, (i + 1, e + 1)) for e in xrange(k + 1): if e < k: nfa.add_transition((len(term), e), ANY, (len(term), e + 1)) nfa.add_final_state((len(term), e)) return nfa