library(tidyverse)

d <- data.frame( name = c(“太郎”, “花子”, “三郎”, “良子”, “次郎”, “桜子”, “四郎”, “松子”, “愛子”), school = c(“南”, “南”, “南”, “南”, “南”, “東”, “東”, “東”, “東”), teacher = c(“竹田”, “竹田”, “竹田”, “竹田”, “佐藤”, “佐藤”, “佐藤”, “鈴木”, “鈴木”), gender = c(“男”, “女”, “男”, “女”, “男”, “女”, “男”, “女”, “女”), math = c(4, 3, 2, 4, 3, 4, 5, 4, 5), reading = c(1, 5, 2, 4, 5, 4, 1, 5, 4) )

library(DT) datatable(d)

d |>select(name,math) #1

d |>select(-gender)#2

d |>slice(3,4,5,6)#3

d |>arrange(name)#4

d |>arrange(desc(math))#5

d |>arrange(desc(math),desc(reading))#6

d |>select(name,reading)#7

d |>summarize(math_mean = mean(math))#8

d |>group_by(teacher)|>summarize(math_mean = mean(math))#9

d |>filter(gender ==“女”)|>select(-school,-teacher)#10

d |>filter(school==“南”,gender ==“男”)#11

d |>group_by(teacher)|>filter(n()>=3)#12

d |>mutate(total = math+reading)#13

d |>mutate(math100 = math*20)#14