group_by(test, Species)## # A tibble: 6 × 5## # Groups: Species [3]## Sepal.Length Sepal.Width Petal.Length...1.9 virginica summarise(group_by(test, Species),mean(Sepal.Length), sd(Sepal.Length))## # A tibble...shift + M)test |> + group_by(Species) |> + summarise(mean(Sepal.Length), sd(Sepal.Length))# A tibble...值dplyr处理关系数据即将2个表进行连接,演示数据来自生信星球1.內连inner_join,取交集2.左连left_join3.全连full_join4.半连接:返回能够与y表匹配的x表所有记录semi_join5...()函数则需要两个数据框有相同的行数> test1 <- data.frame(x = c('b','e','f','x'), + z = c("A","B","