我们可以通过paste将第一个向量（v1）中的值作为单个模式来使用grep，以匹配和子集化来自主向量'v2'的值

grep(paste(v1, collapse = "|"), v2, value = TRUE)

• 输出

[1] "December 2022/File1.xlsx" "December 2022/File2.xlsx" 
[3] "November 2022/File1.xlsx" "November 2022/File2.xlsx"

或者从第二个向量中删除子字符串后缀，使用%in%创建一个逻辑向量以将"v2"作为子集

v2[trimws(v2, whitespace = "/.*") %in% v1]

• 输出

[1] "December 2022/File1.xlsx" "December 2022/File2.xlsx"
[3] "November 2022/File1.xlsx" "November 2022/File2.xlsx"

我们可以Vectorizegrepl并在outer中使用它。

l2[colSums(outer(l1, l2, Vectorize(grepl))) > 0]
# [1] "December 2022/File1.xlsx" "December 2022/File2.xlsx"
# [3] "November 2022/File1.xlsx" "November 2022/File2.xlsx"

另一个选项是将“匿名”Vectorize与grep一起使用

as.vector(Vectorize(\(x) grep(x, list1, value=T))(val))
[1] "December 2022/File1.xlsx" "December 2022/File2.xlsx"
[3] "November 2022/File1.xlsx" "November 2022/File2.xlsx"

接近于sapply和grep

as.vector(sapply(val, grep, list1, value=T))
[1] "December 2022/File1.xlsx" "December 2022/File2.xlsx"
[3] "November 2022/File1.xlsx" "November 2022/File2.xlsx"

数据

val <- c("December 2022","November 2022")
list1 <- c("December 2022/File1.xlsx","December 2022/File2.xlsx","October 2022/File1.xlsx",
"October 2022/File2.xlsx","November 2022/File1.xlsx","November 2022/File2.xlsx")