Day-6 骆栢维
2019-11-27 本文已影响0人
Norville
R包
安装加载R包
> options("repos" = c(CRAN="https://mirrors.tuna.tsinghua.edu.cn/CRAN/"))
>
> options(BioC_mirror="https://mirrors.ustc.edu.cn/bioc/")
>
> install.packages("dplyr")
WARNING: Rtools is required to build R packages but is not currently installed. Please download and install the appropriate version of Rtools before proceeding:
https://cran.rstudio.com/bin/windows/Rtools/
trying URL 'https://mirrors.tuna.tsinghua.edu.cn/CRAN/bin/windows/contrib/3.6/dplyr_0.8.3.zip'
Content type 'application/zip' length 3266767 bytes (3.1 MB)
downloaded 3.1 MB
package ‘dplyr’ successfully unpacked and MD5 sums checked
The downloaded binary packages are in
C:\Users\luobo\AppData\Local\Temp\RtmpMJbEb9\downloaded_packages
> library(dplyr)
载入程辑包：‘dplyr’
The following objects are masked from ‘package:stats’:
filter, lag
The following objects are masked from ‘package:base’:
intersect, setdiff, setequal, union
Warning message:
程辑包‘dplyr’是用R版本3.6.1 来建造的
>
> library(dplyr)#载入R包，便于后面函数使用
dplyr五个基本函数
新增列mutate()
> mutate(test, new = Sepal.Length * Sepal.Width)
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
3 7.0 3.2 4.7 1.4 versicolor
4 6.4 3.2 4.5 1.5 versicolor
5 6.3 3.3 6.0 2.5 virginica
6 5.8 2.7 5.1 1.9 virginica
new
1 17.85
2 14.70
3 22.40
4 20.48
5 20.79
6 15.66
按列筛选
按列号
> select(test,c(2,4))
Sepal.Width Petal.Width
1 3.5 0.2
2 3.0 0.2
51 3.2 1.4
52 3.2 1.5
101 3.3 2.5
102 2.7 1.9
按名
> select(test,Petal.Length)
Petal.Length
1 1.4
2 1.4
51 4.7
52 4.5
101 6.0
102 5.1
筛选行
> filter(test, Species == "setosa"&Sepal.Length < 5 )
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
1 4.9 3 1.4 0.2 setosa
排序
> arrange(test, Sepal.Width)# 默认升序
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
1 5.8 2.7 5.1 1.9 virginica
2 4.9 3.0 1.4 0.2 setosa
3 7.0 3.2 4.7 1.4 versicolor
4 6.4 3.2 4.5 1.5 versicolor
5 6.3 3.3 6.0 2.5 virginica
6 5.1 3.5 1.4 0.2 setosa
> arrange(test, desc(Sepal.Width))# 降序
Sepal.Length Sepal.Width Petal.Length Petal.Width Species
1 5.1 3.5 1.4 0.2 setosa
2 6.3 3.3 6.0 2.5 virginica
3 7.0 3.2 4.7 1.4 versicolor
4 6.4 3.2 4.5 1.5 versicolor
5 4.9 3.0 1.4 0.2 setosa
6 5.8 2.7 5.1 1.9 virginica
汇总
> group_by(test,Species)
# A tibble: 6 x 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))
# A tibble: 3 x 3
Species `mean(Sepal.Length)` `sd(Sepal.Length)`#mean代表平均数，sd表示标准差
<fct> <dbl> <dbl>
1 setosa 5 0.141
2 versicolor 6.7 0.424
3 virginica 6.05 0.354
