替换列[重复]中的元素名称

Question

这个问题在这里已有答案：

• MATCH function in r [duplicate] 1回答

我有两个数据帧df1

structure(list(d.x = structure(c(1L, 2L, 3L, NA, NA, NA, NA, 
NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 
NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA), .Label = c("Sample1", 
"Sample2", "Sample3"), class = "factor"), d.Name = structure(c(1L, 
2L, 3L, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 
NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 
NA, NA, NA, NA), .Label = c("A", "B", "C"), class = "factor")), .Names = c("d.x", 
"d.Name"), row.names = c(NA, -37L), class = "data.frame")

DF2

structure(list(d.ID = structure(c(1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L), .Label = c("Sample1", 
"Sample2", "Sample3"), class = "factor")), .Names = "d.ID", row.names =c(NA, 
-37L), class = "data.frame")

我想用df1文件的相应名称替换df2中的所有名称，因此对于示例Sample1将命名为A.

Answer 1

您可以使用match()如下：

df2$d.Id.New <- df1$d.Name[match(df2$d.ID, df1$d.x)]

这将在df2中创建一个新列，其中包含来自df1的匹配值：

> head(df2)
     d.ID d.Id.New
1 Sample1        A
2 Sample1        A
3 Sample1        A
4 Sample1        A
5 Sample1        A
6 Sample1        A