Grammalecte  Diff

    'œ': 'oe',  'æ': 'ae', 
})

def cleanWord (sWord):
    "word simplication before calculating distance between words"
    return sWord.lower().translate(_xTransChars).replace("eau", "o").replace("au", "o")


def distanceDamerauLevenshtein (s1, s2):
    "distance of Damerau-Levenshtein between <s1> and <s2>"
    # https://fr.wikipedia.org/wiki/Distance_de_Damerau-Levenshtein
    d = {}
    nLen1 = len(s1)
    nLen2 = len(s2)
    for i in range(-1, nLen1+1):
        d[i, -1] = i + 1
    for j in range(-1, nLen2+1):
        d[-1, j] = j + 1
    for i in range(nLen1):
        for j in range(nLen2):
            nCost = 0  if s1[i] == s2[j]  else 1
            d[i, j] = min(
                d[i-1, j]   + 1,        # Deletion
                d[i,   j-1] + 1,        # Insertion
                d[i-1, j-1] + nCost,    # Substitution
            )
            if i and j and s1[i] == s2[j-1] and s1[i-1] == s2[j]:
                d[i, j] = min(d[i, j], d[i-2, j-2] + nCost)     # Transposition
    return d[nLen1-1, nLen2-1]


def showDistance (s1, s2):
    s1b = cleanWord(s1);
    s2b = cleanWord(s2);
    print(f"Distance: {s1} / {s2} = {distanceDamerauLevenshtein(s1, s2)}")
    print(f"Distance: {s1b} / {s2b} = {distanceDamerauLevenshtein(s1b, s2b)}")


def distanceSift4 (s1, s2, nMaxOffset=5):
    "implementation of general Sift4."
    # https://siderite.blogspot.com/2014/11/super-fast-and-accurate-string-distance.html
    if not s1:
        return len(s2)
    if not s2:
        return len(s1)
    nLen1, nLen2 = len(s1), len(s2)
    i1, i2 = 0, 0   # Cursors for each string
    nLargestCS = 0  # Largest common substring
    nLocalCS = 0    # Local common substring
    nTrans = 0      # Number of transpositions ('ab' vs 'ba')
    lOffset = []    # Offset pair array, for computing the transpositions
 
    while i1 < nLen1 and i2 < nLen2:
        if s1[i1] == s2[i2]:
            nLocalCS += 1
            # Check if current match is a transposition
            bTrans = False
            i = 0
            while i < len(lOffset):
                t = lOffset[i]
                if i1 <= t[0] or i2 <= t[1]:
                    bTrans = abs(i2-i1) >= abs(t[1] - t[0])
                    if bTrans:
                        nTrans += 1
                    elif not t[2]:
                        t[2] = True
                        nTrans += 1
                    break
                elif i1 > t[1] and i2 > t[0]:
                    del lOffset[i]
                else:
                    i += 1
            lOffset.append([i1, i2, bTrans])
        else:
            nLargestCS += nLocalCS
            nLocalCS = 0
            if i1 != i2:
                i1 = i2 = min(i1, i2)
            for i in range(nMaxOffset):
                if i1 + i >= nLen1 and i2 + i >= nLen2:
                    break
                elif i1 + i < nLen1 and s1[i1+i] == s2[i2]:
                    i1 += i - 1
                    i2 -= 1
                    break
                elif i2 + i < nLen2 and s1[i1] == s2[i2+i]:
                    i2 += i - 1
                    i1 -= 1
                    break
        i1 += 1
        i2 += 1
        if i1 >= nLen1 or i2 >= nLen2:
            nLargestCS += nLocalCS
            nLocalCS = 0
            i1 = i2 = min(i1, i2)
    nLargestCS += nLocalCS
    return round(max(nLen1, nLen2) - nLargestCS + nTrans)


# Method: Remove Useless Chars

_dVovels = {
    'a': '',  'e': '',  'i': '',  'o': '',  'u': '',  'y': '',
    'à': '',  'é': '',  'î': '',  'ô': '',  'û': '',  'ÿ': '',
    'â': '',  'è': '',  'ï': '',  'ö': '',  'ù': '',  'ŷ': '',
    'ä': '',  'ê': '',  'í': '',  'ó': '',  'ü': '',  'ý': '',
    'á': '',  'ë': '',  'ì': '',  'ò': '',  'ú': '',  'ỳ': '',
    'ā': '',  'ē': '',  'ī': '',  'ō': '',  'ū': '',  'ȳ': '',
    'h': '',  'œ': '',  'æ': ''
 }

_xTransVovels = str.maketrans(_dVovels)


aVovels = frozenset(_dVovels.keys())


def shrinkWord (sWord):
    "remove vovels and h"
    return sWord[0:1].replace("h", "") + sWord[1:].translate(_xTransVovels)


# Similar chars

d1to1 = {
    "1": "liîLIÎ",
    "2": "zZ",
    "3": "eéèêEÉÈÊ",