宽数据变长数据

head(iris)

##   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          4.7         3.2          1.3         0.2  setosa
## 4          4.6         3.1          1.5         0.2  setosa
## 5          5.0         3.6          1.4         0.2  setosa
## 6          5.4         3.9          1.7         0.4  setosa

library(tidyverse)

## ── Attaching core tidyverse packages ────────────────────────────────────── tidyverse 2.0.0 ──
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## ✔ lubridate 1.9.3     ✔ tidyr     1.3.0
## ✔ purrr     1.0.2     
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## ℹ Use the conflicted package (<http://conflicted.r-lib.org/>) to force all conflicts to become errors
```r

#长数据变宽数据
head(gather(iris,key = "key",value = "value",-Species),10)
```r

##    Species          key value
## 1   setosa Sepal.Length   5.1
## 2   setosa Sepal.Length   4.9
## 3   setosa Sepal.Length   4.7
## 4   setosa Sepal.Length   4.6
## 5   setosa Sepal.Length   5.0
## 6   setosa Sepal.Length   5.4
## 7   setosa Sepal.Length   4.6
## 8   setosa Sepal.Length   5.0
## 9   setosa Sepal.Length   4.4
## 10  setosa Sepal.Length   4.9

library(reshape)
```r

## 
## 载入程辑包：'reshape'
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## 
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##     expand, smiths
```r

head(melt(iris,id=c("Species")),5)
```r

##   Species     variable value
## 1  setosa Sepal.Length   5.1
## 2  setosa Sepal.Length   4.9
## 3  setosa Sepal.Length   4.7
## 4  setosa Sepal.Length   4.6
## 5  setosa Sepal.Length   5.0
```r

head(melt(iris,id=5),5)
```r

##   Species     variable value
## 1  setosa Sepal.Length   5.1
## 2  setosa Sepal.Length   4.9
## 3  setosa Sepal.Length   4.7
## 4  setosa Sepal.Length   4.6
## 5  setosa Sepal.Length   5.0
```r

library(tidyr)
#1:4列合并并命名为variable
pivot_longer(iris,cols = 1:4,names_to = "variable",values_to = "count")
```r

## # A tibble: 600 × 3
##    Species variable     count
##    <fct>   <chr>        <dbl>
##  1 setosa  Sepal.Length   5.1
##  2 setosa  Sepal.Width    3.5
##  3 setosa  Petal.Length   1.4
##  4 setosa  Petal.Width    0.2
##  5 setosa  Sepal.Length   4.9
##  6 setosa  Sepal.Width    3  
##  7 setosa  Petal.Length   1.4
##  8 setosa  Petal.Width    0.2
##  9 setosa  Sepal.Length   4.7
## 10 setosa  Sepal.Width    3.2
## # ℹ 590 more rows
```r