>7)
dplyr::filter(mtcars,mpg>21)
dplyr::filter(mtcars,cyl == 6,mpg>21)
dplyr::filter(mtcars,cyl == c(...arrange(desc(num)) %>%
ggplot(aes(x=num)) + geom_bar()
x %>% count(Province)
八、集合运算
a=data.frame(x1=c(..."A","B","C"),x2=c(1,2,3))
a
b=data.frame(x1=c("A","B","D"),x3=c(T,F,T))
b
dplyr::left_join(a,b,by="x1