下述法典用于编前第9版。 难道这是不可能的吗?
df = data.frame(x = letters[1:26], y=abs(rnorm(26)))
ggplot(df, aes(x=x, y=y)) + geom_bar() + geom_vline(xintercept= m )
我有以下错误:
Error in get(as.character(FUN), mode = "function", envir = envir) : object m of mode function was not found