定义和用法

levenshtein() 函数返回两个字符串之间的 Levenshtein 距离。

Levenshtein 距离，又称编辑距离，指的是两个字符串之间，由一个转换成另一个所需的最少编辑操作次数。许可的编辑操作包括将一个字符替换成另一个字符，插入一个字符，删除一个字符。

例如把 kitten 转换为 sitting：

levenshtein() 函数给每个操作（替换、插入和删除）相同的权重。不过，您可以通过设置可选的 insert、replace、delete 参数，来定义每个操作的代价。

转换规则

B ----> B unless at the end of word after "m", as in "dumb", "McComb"

C ----> X (sh) if "-cia-" or "-ch-" S if "-ci-", "-ce-", or "-cy-" SILENT if "-sci-", "-sce-", or "-scy-" K otherwise, including in "-sch-"

D ----> J if in "-dge-", "-dgy-", or "-dgi-" T otherwise

F ----> F

G ----> SILENT if in "-gh-" and not at end or before a vowel in "-gn" or "-gned" in "-dge-" etc., as in above rule J if before "i", or "e", or "y" if not double "gg" K otherwise

H ----> SILENT if after vowel and no vowel follows or after "-ch-", "-sh-", "-ph-", "-th-", "-gh-" H otherwise

J ----> J

K ----> SILENT if after "c" K otherwise

L ----> L

M ----> M

N ----> N