python正则表达式匹配两个字符串

Question

我想检查两个字符串是否相似。。。。 例如：

string1 = "Select a valid choice. **aaaa** is not one of the available choices."
string2 = "Select a valid choice. **bbbb** is not one of the available choices."

或者

string3 = "Ensure this value has at most 30 characters (it has 40 chars)."
string4 = "Ensure this value has at most 60 characters (it has 110 chars)."

如果我比较string1和string2，它应该返回True；如果我比较string1和string3，它应该返回False。你知道吗

Answer 1

你可以使用Levenshtein distance

def lev(s1, s2):
    if len(s1) < len(s2):
        return lev(s2, s1)

    # len(s1) >= len(s2)
    if len(s2) == 0:
        return len(s1)

    previous_row = xrange(len(s2) + 1)
    for i, c1 in enumerate(s1):
        current_row = [i + 1]
        for j, c2 in enumerate(s2):
            insertions = previous_row[j + 1] + 1 # j+1 instead of j since previous_row and current_row are one character longer
            deletions = current_row[j] + 1       # than s2
            substitutions = previous_row[j] + (c1 != c2)
            current_row.append(min(insertions, deletions, substitutions))
        previous_row = current_row

    return previous_row[-1]

string1 = "Select a valid choice. aaaa is not one of the available choices."
string2 = "Select a valid choice. bbbb is not one of the available choices."
string3 = "Ensure this value has at most 30 characters (it has 40 chars)."
string4 = "Ensure this value has at most 60 characters (it has 110 chars)."

print lev(string1, string2) # => 4
print lev(string3, string4) # => 3
print lev(string1, string3) # => 49

从here复制的代码