悬赏 1 个论坛币 未解决
structure(c(2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L,
2L, 2L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L,
1L, 2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 1L), .Label = c("after",
"before"), class = "factor")
以上是用edit调用的编辑器中的描述,R默认after在前,before在后,怎么样修改才能before在前,after在后