代码如下:
colnames(tab)
>[1] "Year" "Class" "1" "2" "3" "4" "5" "6" "7" "8" "9" "10" "11" "12"
>tab<-tab[,c("Year","Class",as.character(0:9),">=10")]
>c("Year","Class",as.character(0:9),">=10")
>[1] "Year" "Class" "0" "1" "2" "3" "4" "5" "6" "7" "8" "9" ">=10"
出现错误,Error in `[.data.frame`(tab, , c("Year", "Class", as.character(0:9), ">=10")) :
undefined columns selected