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(“包”)或者BiocManager::install(“包”)。#取决于你要安装的包存在于CRAN网站还是Biocductor,可以在歌搜到
install.packages("dplyr")
library(dplyr) #在使用前需要调取‘dplyr’包
> test <- iris[c(1:2,51:52,101:102),]
> mutate(test,new= Sepal.Length * Sepal.Width) #新增加列
Sepal.Length Sepal.Width Petal.Length Petal.Width Species new
1 5.1 3.5 1.4 0.2 setosa 17.85
2 4.9 3.0 1.4 0.2 setosa 14.70
51 7.0 3.2 4.7 1.4 versicolor 22.40
52 6.4 3.2 4.5 1.5 versicolor 20.48
101 6.3 3.3 6.0 2.5 virginica 20.79
102 5.8 2.7 5.1 1.9 virginica 15.66
> select(test,1)#按列号筛选,筛选第一列
Sepal.Length
1 5.1
2 4.9
51 7.0
52 6.4
101 6.3
102 5.8
> select(test,c(1,5))
Sepal.Length Species
1 5.1 setosa
2 4.9 setosa
51 7.0 versicolor
52 6.4 versicolor
101 6.3 virginica
102 5.8 virginica
> select(test,Sepal.Length)#按列名筛选
Sepal.Length
1 5.1
2 4.9
51 7.0
52 6.4
101 6.3
102 5.8
> select(test, Petal.Length, Petal.Width)
Petal.Length Petal.Width
1 1.4 0.2
2 1.4 0.2
51 4.7 1.4
52 4.5 1.5
101 6.0 2.5
102 5.1 1.9
> vars <- c("Petal.Length", "Petal.Width")
> select(test, one_of(vars))
Petal.Length Petal.Width
1 1.4 0.2
2 1.4 0.2
51 4.7 1.4
52 4.5 1.5
101 6.0 2.5
102 5.1 1.9
> filter(test, Species == "setosa") #filter 筛选行
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
1 5.1 3.5 1.4 0.2 setosa
2 4.9 3.0 1.4 0.2 setosa
> filter(test, Species == "setosa"&Sepal.Length > 5 )#筛选行同时列>5的
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
1 5.1 3.5 1.4 0.2 setosa
> filter(test, Species %in% c("setosa","versicolor"))
Sepal.Length Sepal.Width Petal.Length
1 5.1 3.5 1.4
2 4.9 3.0 1.4
3 7.0 3.2 4.7
4 6.4 3.2 4.5
Petal.Width Species
1 0.2 setosa
2 0.2 setosa
3 1.4 versicolor
4 1.5 versicolor
> arrange(test, Sepal.Length) #arrange排序,默认从小到大排序
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
1 4.9 3.0 1.4 0.2 setosa
2 5.1 3.5 1.4 0.2 setosa
3 5.8 2.7 5.1 1.9 virginica
4 6.3 3.3 6.0 2.5 virginica
5 6.4 3.2 4.5 1.5 versicolor
6 7.0 3.2 4.7 1.4 versicolor
> arrange(test, desc(Sepal.Length)) #用desc从大到小
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
1 7.0 3.2 4.7 1.4 versicolor
2 6.4 3.2 4.5 1.5 versicolor
3 6.3 3.3 6.0 2.5 virginica
4 5.8 2.7 5.1 1.9 virginica
5 5.1 3.5 1.4 0.2 setosa
6 4.9 3.0 1.4 0.2 setosa
> summarise(test, mean(Sepal.Length), sd(Sepal.Length)) #计算Sepal.Length的平均值和标准差
mean(Sepal.Length) sd(Sepal.Length)
1 5.916667 0.8084965
> group_by(test, Species)
# A tibble: 6 × 5
# Groups: Species [3]
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
<dbl> <dbl> <dbl> <dbl> <fct>
1 5.1 3.5 1.4 0.2 setosa
2 4.9 3 1.4 0.2 setosa
3 7 3.2 4.7 1.4 versicolor
4 6.4 3.2 4.5 1.5 versicolor
5 6.3 3.3 6 2.5 virginica
6 5.8 2.7 5.1 1.9 virginica
> summarise(group_by(test, Species),mean(Sepal.Length), sd(Sepal.Length)) #按照Species分组,计算每组Sepal.Length的平均值和标准差
# A tibble: 3 × 3
Species `mean(Sepal.Length)` `sd(Sepal.Length)`
<fct> <dbl> <dbl>
1 setosa 5 0.141
2 versicolor 6.7 0.424
3 virginica 6.05 0.354
> test %>%
+ group_by(Species) %>%
+ summarise(mean(Sepal.Length), sd(Sepal.Length)) #管道操作,%>%,同上面的命令一样
# A tibble: 3 × 3
Species `mean(Sepal.Length)` `sd(Sepal.Length)`
<fct> <dbl> <dbl>
1 setosa 5 0.141
2 versicolor 6.7 0.424
3 virginica 6.05 0.354
> count(test,Species) #count计算某列的unique值
Species n
1 setosa 2
2 versicolor 2
3 virginica 2
> #dplyr处理关系数据
> ## 将两个表进行连接
> test1 <- data.frame(x = c('b','e','f','x'),
+ z = c("A","B","C",'D'))
> test1
x z
1 b A
2 e B
3 f C
4 x D
> test2 <- data.frame(x = c('a','b','c','d','e','f'),
+ y = c(1,2,3,4,5,6))
> test2
x y
1 a 1
2 b 2
3 c 3
4 d 4
5 e 5
6 f 6
>
> inner_join(test1, test2, by = "x") #inner_join,取交集
x z y
1 b A 2
2 e B 5
3 f C 6
> left_join(test1, test2, by = 'x') #test1在左
x z y
1 b A 2
2 e B 5
3 f C 6
4 x D NA
> left_join(test2, test1, by = 'x') #test2在左
x y z
1 a 1 <NA>
2 b 2 A
3 c 3 <NA>
4 d 4 <NA>
5 e 5 B
6 f 6 C
> full_join( test1, test2, by = 'x') #全连
x z y
1 b A 2
2 e B 5
3 f C 6
4 x D NA
5 a <NA> 1
6 c <NA> 3
7 d <NA> 4
> semi_join(x = test1, y = test2, by = 'x')#半连接,返回能够与y表匹配的X表的所有记录
x z
1 b A
2 e B
3 f C
> semi_join(x = test2, y = test1, by = 'x')
x y
1 b 2
2 e 5
3 f 6
> anti_join(x = test2, y = test1, by = 'x') #反连接,返回无法与y表匹配的所有记录
x y
1 a 1
2 c 3
3 d 4
> #合并数据框
> test1 <- data.frame(x = c(1,2,3,4), y = c(10,20,30,40))
> test1
x y
1 1 10
2 2 20
3 3 30
4 4 40
> test2 <- data.frame(x = c(5,6), y = c(50,60))
> test2
x y
1 5 50
2 6 60
> test3 <- data.frame(z = c(100,200,300,400))
> test3
z
1 100
2 200
3 300
4 400
> bind_rows(test1, test2)
x y
1 1 10
2 2 20
3 3 30
4 4 40
5 5 50
6 6 60
> bind_cols(test1, test3) #行合并时需要两个数据框的列数相同,列合并时需要两个数据框的行相同
x y z
1 1 10 100
2 2 20 200
3 3 30 300
4 4 40 400
原创声明:本文系作者授权腾讯云开发者社区发表,未经许可,不得转载。
如有侵权,请联系 cloudcommunity@tencent.com 删除。
原创声明:本文系作者授权腾讯云开发者社区发表,未经许可,不得转载。
如有侵权,请联系 cloudcommunity@tencent.com 删除。