R 기본 통계 명령어

> data(iris)
> 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
> summary(iris)
  Sepal.Length    Sepal.Width     Petal.Length  
 Min.   :4.300   Min.   :2.000   Min.   :1.000  
 1st Qu.:5.100   1st Qu.:2.800   1st Qu.:1.600  
 Median :5.800   Median :3.000   Median :4.350  
 Mean   :5.843   Mean   :3.057   Mean   :3.758  
 3rd Qu.:6.400   3rd Qu.:3.300   3rd Qu.:5.100  
 Max.   :7.900   Max.   :4.400   Max.   :6.900  
  Petal.Width          Species  
 Min.   :0.100   setosa    :50  
 1st Qu.:0.300   versicolor:50  
 Median :1.300   virginica :50  
 Mean   :1.199                  
 3rd Qu.:1.800                  
 Max.   :2.500  

 
> mean(iris$Petal.Width)
[1] 1.199333
> median(iris$Petal.Width)
[1] 1.3
> sd(iris$Petal.Width)
[1] 0.7622377
> var(iris$Petal.Width)
[1] 0.5810063
> quantile(iris$Petal.Width,1/4)
25% 
0.3 
> quantile(iris$Petal.Width, 3/4)
75% 
1.8 
> max(iris$Petal.Width)
[1] 2.5
> min(iris$Petal.Width)
[1] 0.1