删除“。”后的部分string

这是一个简单的问题，但我不明白我做错了什么。 我工作在R与login号如variablesa

>a <- c("NM_020506.1","NM_020519.1","NM_001030297.2","NM_010281.2","NM_011419.3", "NM_053155.2") 

要从biomart软件包中获取信息，我需要删除.1等。 我通常这样做这个代码：

 > b <- sub("..*","",a) >[1] "" "" "" "" "" "" 

但是正如你所看到的，这不是这个variables的正确方法。 谁能帮我这个？

Answer 1

你只需要逃避一段时间：

 a <- c("NM_020506.1","NM_020519.1","NM_001030297.2","NM_010281.2","NM_011419.3", "NM_053155.2") gsub("\\..*","",a) [1] "NM_020506" "NM_020519" "NM_001030297" "NM_010281" "NM_011419" "NM_053155" 

Answer 2

你可以这样做：

 sub("*\\.[0-9]", "", a) 

要么

 library(stringr) str_sub(a, start=1, end=-3) 

Answer 3

我们可以假装他们是文件名并删除扩展名 ：

 tools::file_path_sans_ext(a) # [1] "NM_020506" "NM_020519" "NM_001030297" "NM_010281" "NM_011419" "NM_053155"