From 1096f2c86ea0e07383b97c4aa8b148ca841cc0f9 Mon Sep 17 00:00:00 2001 From: Mattias Andrée Date: Thu, 4 Oct 2012 22:11:33 +0200 Subject: spelling correction mechanism with weigthed character change --- ponysay.py | 162 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 162 insertions(+) (limited to 'ponysay.py') diff --git a/ponysay.py b/ponysay.py index 1ebd9c3..71ea42e 100755 --- a/ponysay.py +++ b/ponysay.py @@ -1710,6 +1710,168 @@ class UCS(): +''' +Class used for correcting spellos and typos, + +Note that this implementation will not find that correctly spelled word are correct faster than it corrects words. +It is also limited to words of size 0 to 127 (inclusive) +''' +class SpelloCorrecter: # Naïvely and quickly proted and adapted from optimised Java, may not be the nicest, or even fast, Python code + def __init__(self, directories, ending): + self.weights = {'k' : {'c' : 0.25, 'g' : 0.75, 'q' : 0.125}, + 'c' : {'k' : 0.25, 'g' : 0.75, 's' : 0.5, 'z' : 0.5, 'q' : 0.125}, + 's' : {'z' : 0.25, 'c' : 0.5}, + 'z' : {'s' : 0.25, 'c' : 0.5}, + 'g' : {'k' : 0.75, 'c' : 0.75, 'q' : 0.9}, + 'o' : {'u' : 0.5}, + 'u' : {'o' : 0.5, 'v' : 0.75, 'w' : 0.5}, + 'b' : {'v' : 0.75}, + 'v' : {'b' : 0.75, 'w' : 0.5, 'u' : 0.7}, + 'w' : {'v' : 0.5, 'u' : 0.5}, + 'q' : {'c' : 0.125, 'k' : 0.125, 'g' : 0.9}} + + self.corrections = None + self.dictionary = [None] * 513 + self.reusable = [0] * 512 + self.dictionaryEnd = 512 + self.closestDistance = 0 + + self.M = [None] * 128 + for y in range(0, 128): + self.M[y] = [0] * 128 + self.M[y][0] = y + m0 = self.M[0] + x = 127 + while x > -1: + m0[x] = x + x -= 1 + + previous = "" + self.dictionary[-1] = previous; + + for directory in directories: + for filename : os.listdir(directory): + if (not endswith(filename, ending)) or (len(filename) - len(ending) > 127): + continue + proper = filename[:-len(ending)] + + if dictionaryEnd == 0: + dictionaryEnd = len(self.dictionary) + self.reusable = [0] * dictionaryEnd + self.reusable + self.dictionary = [None] * dictionaryEnd + self.dictionary + + dictionaryEnd -= 1 + dictionary[dictionaryEnd] = proper + prevCommon = min(len(previous), len(proper)) + for i in range(0, prevCommon): + if previous[i] != proper[i]: + prevCommon = i + break + previous = dictionary[dictionaryEnd] + reusable[dictionaryEnd] = prevCommon + + + ''' + Finds the closests correct spelled word. + The input is just one word, and the output is tuple + with a list of the closest spellings, and the weigthed distance. + ''' + def correct(self, used): + if len(used) < 127: + return ([used], 0) + + __correct(used) + return (seld.corrections, self.closestDistance) + + + def __correct(self, used): + self.closestDistance = 0x7FFFFFFF + previous = self.dictionary[-1] + prevLen = 0 + usedLen = len(used) + + proper = None + prevCommon = 0 + + d = len(self.dictionary) + while d > self.dictionaryEnd: + d -= 1 + proper = self.dictionary[d] + if abs(len(proper) - usedLen) <= self.closestDistance: + if previous == self.dictionary[d + 1]: + prevCommon = self.reusable[d]; + else: + prevCommon = min(prevLen, len(proper)) + for i in range(0, prevCommon): + if previous[i] != proper[i]: + prevCommon = i + break + + skip = min(prevLen, len(proper)) + i = prevCommon + while i < skip: + for u in range(0, usedLen): + if (used[u] == previous[i]) or (used[u] == proper[i]): + skip = i + break + i += 1 + + common = min(skip, min(usedLen, len(proper))) + for i in range(0, common): + if used[i] != proper[i]: + common = i + break + + distance = self.__distance(proper, skip, proper.length, used, common, usedLen) + + if self.closestDistance > distance: + self.closestDistance = distance + corrections = [proper] + elif self.closestDistance == distance: + corrections.append(proper) + + previous = proper; + if distance >= 0x7FFFFF00: + prevLen = distance & 255 + else: + prevLen = len(proper) + + + def __distance(self, proper, y0, yn, used, x0, xn): + my = self.M[y0] + for y in range(y0, yn): + best = 0x7FFFFFFF + p = proper[y] + myy = self.M[y + 1] # only one array bound check, and at most one + ☺ + x = x0 + while x < xn: + change = my[x] + u = used[x] + if p == u: + # commence black magick … twilight would be so disappointed + x += 1 + myy[x] = change + best = min(best, change) + remove = myy[x] + add = my[x + 1] + + cw = 1 + if my[x] in self.weights: + if p in self.weights[u]: + cw = self.weights[u][p] + + myy[x] = min(cw + change, 1 + min(remove, add)) + if best > myy[x]: + best = myy[x] + + if best > self.closestDistance: + return 0x7FFFFFFF | y + my = myy + return my[xn] + + + + ''' The user's home directory ''' -- cgit