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Cloft X
Asked: 2023-12-21 00:55:46 +0800 CST

如何在 R 中查找两个大小不等的向量之间的字符串匹配？

  • 772

我有两个带有字符串的向量，如下所示：

x <- c("Zimbabwe (Rhodesia)", "India", "Equatorial Guinea", "United States")

y <- c("Zimbabwe", "India", "Guinea")

我想获得一个向量，其中包含和之间不完全匹配的字符串。理想的结果是：xy

"Zimbabwe (Rhodesia)" "Zimbabwe" "Equatorial Guinea" "Guinea" "United States"

我试图在这里巩固一些概念 - 我知道我可以用来grep(paste(y, collapse = "|")获取向量的部分匹配，并使用锚点来查找给定字符串的精确匹配。但如何整合它们呢？

我该怎么做呢？

3 个回答

  1. Best Answer

    一种选择是使用集合运算，即使用并集和交集的集合差：

    x <- c("Zimbabwe (Rhodesia)", "India", "Equatorial Guinea", "United States")

y <- c("Zimbabwe", "India", "Guinea")

setdiff(union(x, y), intersect(x, y))
#> [1] "Zimbabwe (Rhodesia)" "Equatorial Guinea"   "United States"      
#> [4] "Zimbabwe"            "Guinea"
    • 5

  2. 另一种可能，可能更直观一些：

    x = c("Zimbabwe (Rhodesia)", "India", "Equatorial Guinea", "United States")
y = c("Zimbabwe", "India", "Guinea")
c(x[!(x %in% y)], y[!(y %in% x)])
#> [1] "Zimbabwe (Rhodesia)" "Equatorial Guinea"   "United States"      
#> [4] "Zimbabwe"            "Guinea"

    创建于 2023 年 12 月 20 日，使用reprex v2.0.2

    按“字母递减”顺序：

    > c(x[!(x %in% y)], y[!(y %in% x)]) |> 
+   { \(.) .[order(., decreasing = TRUE)] }()
[1] "Zimbabwe (Rhodesia)" "Zimbabwe"            "United States"       "Guinea"             
[5] "Equatorial Guinea"
    • 3

  3. 您可以连接并删除重复的：

    c(x,y)[!c(x,y) %in% intersect(x,y)]

[1] "Zimbabwe (Rhodesia)" "Equatorial Guinea"   "United States"       "Zimbabwe"            "Guinea"
    • 0

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