当使用R中的 adist 函数来计算字符串对之间的Levenshtein对齐时，我会得到不同的结果，这取决于我是为每对运行一次函数还是使用向量一次输入几对 . 这是为什么？

Example: 字符串对的转换'knijpen' - 'kneifen'，'grijpen' - 'greifen'和'lopen' - 'laufen'：

attr(adist("knijpen", "kneifen", counts = TRUE), "trafos")
#      [,1]      
# [1,] "MMIMSDMM"

attr(adist("grijpen", "greifen", counts = TRUE), "trafos")
#      [,1]      
# [1,] "MMIMSDMM"

attr(adist("lopen", "laufen", counts = TRUE), "trafos")
#      [,1]    
# [1,] "MSSIMM"

这些与我自己的手动解决方案一致 . 但是，当我使用向量输入字符串时，我得到的结果略有不同：

dutch <- c("knijpen", "grijpen", "lopen")
german <- c("kneifen", "greifen", "laufen")
attr(adist(dutch, german, counts = TRUE), "trafos")
#      [,1]       [,2]       [,3]      
# [1,] "MMIMSDMM" "SSIMSDMM" "SSSSDMMM"
# [2,] "SSIMSDMM" "MMIMSDMM" "SSSSDMMM"
# [3,] "SSSIIMMM" "SSSIIMMM" "MSSIMMM"

此矩阵中的[3,3]元素应对应于 attr(adist("lopen", "laufen", counts = TRUE), "trafos") （即 "MSSIMM" ），但它还有另一个 M . 为什么？

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