R语言安装R包DAY6-Gaozsi

options("repos" = c(CRAN="https://mirrors.tuna.tsinghua.edu.cn/CRAN/")) #对应清华源

options(BioC_mirror="https://mirrors.ustc.edu.cn/bioc/") #对应中科大源

install.packages("dplyr")
library(dplyr)

test <- iris[c(1:2,51:52,101:102),]#取1,2,51,52,101,102行，所有列

mutate(test, new = Sepal.Length * Sepal.Width)

select(test,1)
select(test,c(1,5))
select(test,Sepal.Length)
select(test, Petal.Length, Petal.Width)
vars <- c("Petal.Length", "Petal.Width")
select(test, one_of(vars))

filter(test, Species == "setosa")
filter(test, Species == "setosa"&Sepal.Length > 5)
filter(test, Species %in% c("setosa","versicolor"))

arrange(test, Sepal.Length)#从小到大排序
arrange(test, desc(Sepal.Length))#从大到小

summarise(test, mean(Sepal.Length), sd(Sepal.Length))# 计算Sepal.Length的平均值和标准差
# 先按照Species分组，计算每组Sepal.Length的平均值和标准差
group_by(test, Species)
summarise(group_by(test, Species),mean(Sepal.Length), sd(Sepal.Length))

test %>% #对象
   group_by(Species) %>% #分组
   summarise(mean(Sepal.Length), sd(Sepal.Length))#计算

count(test,Species)

x <- tribble(
   ~key, ~val_x,
  1, "x1",
  2, "x2",
  3, "x3")

y <- tribble(
  ~key, ~val_y,
  1, "y1",
  2, "y2",
  4, "y3")

y1 <- tribble(
  ~key, ~val_y,
  1, "y1",
  2, "y2",
  4, "y4",
  2, "y5")

x %>%  inner_join(y, by = "key")

> left_join(x, y, by = "key")

left_join(x, y1, by = "key")

right_join(x, y, by = "key")

full_join(x, y, by = "key")

semi_join(x =x, y =y, by = 'key')

anti_join(x =x, y =y, by = 'key')

test1 <- data.frame(x = c(1,2,3,4), y = c(10,20,30,40))
test2 <- data.frame(x = c(5,6), y = c(50,60))
test3 <- data.frame(z = c(100,200,300,400))

bind_rows(test1, test2)

bind_cols(test1, test3)