教程来自： 慕课
微生物高通量数据分析入门

学习目标：

filter,arrange,mutate,select函数，R中的管道符%>%的运用

开始吧

使用内置的数据集diamonds作为练习

library(tidyverse)

#filter筛选
diamonds%>%
  filter(color == "D")

diamonds%>%
  filter(color == "D",cut =="Ideal")


#arrange排列，排序
diamonds%>%
  arrange(price)#升序排列

diamonds%>%
  arrange(desc(price))#降序排列

#filter和arrange联合
diamonds%>%
  filter(color == "D")%>%
  arrange(desc(price))
or
arrange(filter(diamonds,color == "D"),desc(price))


#mutate是改变或者增加一个变量
diamonds%>%
  mutate(price*7)#直接在末尾增加一列

diamonds%>%
  mutate(price = price*7) #增加一列并且赋值给原来price列

diamonds%>%
  mutate(price_RMB = price*7)#增加一列名为price_RMB

diamonds%>%
  filter(color == "D")%>%
  mutate(price_RMB = price*7)%>%
  arrange(price_RMB)

#select按列选择
diamonds %>%
  select(color,cut)

#summarise总结
diamonds%>%
  summarise(sum(price))

sum(diamonds$price)
mean(diamonds$price)
#好像这两种方法效果一样。