x<-311 # x=3
x
## [1] 311
3>4
## [1] FALSE
3==4
## [1] FALSE
a<-10
a
## [1] 10
a<-"hello"
a
## [1] "hello"
a<-c(1,2,3)
a
## [1] 1 2 3
max(a)
## [1] 3
min(a)
## [1] 1
mean(a)
## [1] 2
library(dplyr)
## 
## 다음의 패키지를 부착합니다: 'dplyr'
## The following objects are masked from 'package:stats':
## 
##     filter, lag
## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union
mode(a)
## [1] "numeric"
is.numeric(a)
## [1] TRUE
length(a)
## [1] 3
x<-c(1,2)
y<-c("a","b")
xy<-c(x,y)
xy
## [1] "1" "2" "a" "b"
mode(xy)
## [1] "character"
1:5
## [1] 1 2 3 4 5
gender<-c("male", "female", "male")
bloodtype<-c("AB","O","B")
height<-c(170,175,165)
weight<-c(70,65,55)
df<-data.frame(gender,bloodtype,height,weight)
df
##   gender bloodtype height weight
## 1   male        AB    170     70
## 2 female         O    175     65
## 3   male         B    165     55
car<-c("kia", "bmw", "toyota")
df2<-data.frame(df, car)
df2
##   gender bloodtype height weight    car
## 1   male        AB    170     70    kia
## 2 female         O    175     65    bmw
## 3   male         B    165     55 toyota
data(iris)
iris[,c(1:2)]
##     Sepal.Length Sepal.Width
## 1            5.1         3.5
## 2            4.9         3.0
## 3            4.7         3.2
## 4            4.6         3.1
## 5            5.0         3.6
## 6            5.4         3.9
## 7            4.6         3.4
## 8            5.0         3.4
## 9            4.4         2.9
## 10           4.9         3.1
## 11           5.4         3.7
## 12           4.8         3.4
## 13           4.8         3.0
## 14           4.3         3.0
## 15           5.8         4.0
## 16           5.7         4.4
## 17           5.4         3.9
## 18           5.1         3.5
## 19           5.7         3.8
## 20           5.1         3.8
## 21           5.4         3.4
## 22           5.1         3.7
## 23           4.6         3.6
## 24           5.1         3.3
## 25           4.8         3.4
## 26           5.0         3.0
## 27           5.0         3.4
## 28           5.2         3.5
## 29           5.2         3.4
## 30           4.7         3.2
## 31           4.8         3.1
## 32           5.4         3.4
## 33           5.2         4.1
## 34           5.5         4.2
## 35           4.9         3.1
## 36           5.0         3.2
## 37           5.5         3.5
## 38           4.9         3.6
## 39           4.4         3.0
## 40           5.1         3.4
## 41           5.0         3.5
## 42           4.5         2.3
## 43           4.4         3.2
## 44           5.0         3.5
## 45           5.1         3.8
## 46           4.8         3.0
## 47           5.1         3.8
## 48           4.6         3.2
## 49           5.3         3.7
## 50           5.0         3.3
## 51           7.0         3.2
## 52           6.4         3.2
## 53           6.9         3.1
## 54           5.5         2.3
## 55           6.5         2.8
## 56           5.7         2.8
## 57           6.3         3.3
## 58           4.9         2.4
## 59           6.6         2.9
## 60           5.2         2.7
## 61           5.0         2.0
## 62           5.9         3.0
## 63           6.0         2.2
## 64           6.1         2.9
## 65           5.6         2.9
## 66           6.7         3.1
## 67           5.6         3.0
## 68           5.8         2.7
## 69           6.2         2.2
## 70           5.6         2.5
## 71           5.9         3.2
## 72           6.1         2.8
## 73           6.3         2.5
## 74           6.1         2.8
## 75           6.4         2.9
## 76           6.6         3.0
## 77           6.8         2.8
## 78           6.7         3.0
## 79           6.0         2.9
## 80           5.7         2.6
## 81           5.5         2.4
## 82           5.5         2.4
## 83           5.8         2.7
## 84           6.0         2.7
## 85           5.4         3.0
## 86           6.0         3.4
## 87           6.7         3.1
## 88           6.3         2.3
## 89           5.6         3.0
## 90           5.5         2.5
## 91           5.5         2.6
## 92           6.1         3.0
## 93           5.8         2.6
## 94           5.0         2.3
## 95           5.6         2.7
## 96           5.7         3.0
## 97           5.7         2.9
## 98           6.2         2.9
## 99           5.1         2.5
## 100          5.7         2.8
## 101          6.3         3.3
## 102          5.8         2.7
## 103          7.1         3.0
## 104          6.3         2.9
## 105          6.5         3.0
## 106          7.6         3.0
## 107          4.9         2.5
## 108          7.3         2.9
## 109          6.7         2.5
## 110          7.2         3.6
## 111          6.5         3.2
## 112          6.4         2.7
## 113          6.8         3.0
## 114          5.7         2.5
## 115          5.8         2.8
## 116          6.4         3.2
## 117          6.5         3.0
## 118          7.7         3.8
## 119          7.7         2.6
## 120          6.0         2.2
## 121          6.9         3.2
## 122          5.6         2.8
## 123          7.7         2.8
## 124          6.3         2.7
## 125          6.7         3.3
## 126          7.2         3.2
## 127          6.2         2.8
## 128          6.1         3.0
## 129          6.4         2.8
## 130          7.2         3.0
## 131          7.4         2.8
## 132          7.9         3.8
## 133          6.4         2.8
## 134          6.3         2.8
## 135          6.1         2.6
## 136          7.7         3.0
## 137          6.3         3.4
## 138          6.4         3.1
## 139          6.0         3.0
## 140          6.9         3.1
## 141          6.7         3.1
## 142          6.9         3.1
## 143          5.8         2.7
## 144          6.8         3.2
## 145          6.7         3.3
## 146          6.7         3.0
## 147          6.3         2.5
## 148          6.5         3.0
## 149          6.2         3.4
## 150          5.9         3.0
iris[,c(1,3,5)]
##     Sepal.Length Petal.Length    Species
## 1            5.1          1.4     setosa
## 2            4.9          1.4     setosa
## 3            4.7          1.3     setosa
## 4            4.6          1.5     setosa
## 5            5.0          1.4     setosa
## 6            5.4          1.7     setosa
## 7            4.6          1.4     setosa
## 8            5.0          1.5     setosa
## 9            4.4          1.4     setosa
## 10           4.9          1.5     setosa
## 11           5.4          1.5     setosa
## 12           4.8          1.6     setosa
## 13           4.8          1.4     setosa
## 14           4.3          1.1     setosa
## 15           5.8          1.2     setosa
## 16           5.7          1.5     setosa
## 17           5.4          1.3     setosa
## 18           5.1          1.4     setosa
## 19           5.7          1.7     setosa
## 20           5.1          1.5     setosa
## 21           5.4          1.7     setosa
## 22           5.1          1.5     setosa
## 23           4.6          1.0     setosa
## 24           5.1          1.7     setosa
## 25           4.8          1.9     setosa
## 26           5.0          1.6     setosa
## 27           5.0          1.6     setosa
## 28           5.2          1.5     setosa
## 29           5.2          1.4     setosa
## 30           4.7          1.6     setosa
## 31           4.8          1.6     setosa
## 32           5.4          1.5     setosa
## 33           5.2          1.5     setosa
## 34           5.5          1.4     setosa
## 35           4.9          1.5     setosa
## 36           5.0          1.2     setosa
## 37           5.5          1.3     setosa
## 38           4.9          1.4     setosa
## 39           4.4          1.3     setosa
## 40           5.1          1.5     setosa
## 41           5.0          1.3     setosa
## 42           4.5          1.3     setosa
## 43           4.4          1.3     setosa
## 44           5.0          1.6     setosa
## 45           5.1          1.9     setosa
## 46           4.8          1.4     setosa
## 47           5.1          1.6     setosa
## 48           4.6          1.4     setosa
## 49           5.3          1.5     setosa
## 50           5.0          1.4     setosa
## 51           7.0          4.7 versicolor
## 52           6.4          4.5 versicolor
## 53           6.9          4.9 versicolor
## 54           5.5          4.0 versicolor
## 55           6.5          4.6 versicolor
## 56           5.7          4.5 versicolor
## 57           6.3          4.7 versicolor
## 58           4.9          3.3 versicolor
## 59           6.6          4.6 versicolor
## 60           5.2          3.9 versicolor
## 61           5.0          3.5 versicolor
## 62           5.9          4.2 versicolor
## 63           6.0          4.0 versicolor
## 64           6.1          4.7 versicolor
## 65           5.6          3.6 versicolor
## 66           6.7          4.4 versicolor
## 67           5.6          4.5 versicolor
## 68           5.8          4.1 versicolor
## 69           6.2          4.5 versicolor
## 70           5.6          3.9 versicolor
## 71           5.9          4.8 versicolor
## 72           6.1          4.0 versicolor
## 73           6.3          4.9 versicolor
## 74           6.1          4.7 versicolor
## 75           6.4          4.3 versicolor
## 76           6.6          4.4 versicolor
## 77           6.8          4.8 versicolor
## 78           6.7          5.0 versicolor
## 79           6.0          4.5 versicolor
## 80           5.7          3.5 versicolor
## 81           5.5          3.8 versicolor
## 82           5.5          3.7 versicolor
## 83           5.8          3.9 versicolor
## 84           6.0          5.1 versicolor
## 85           5.4          4.5 versicolor
## 86           6.0          4.5 versicolor
## 87           6.7          4.7 versicolor
## 88           6.3          4.4 versicolor
## 89           5.6          4.1 versicolor
## 90           5.5          4.0 versicolor
## 91           5.5          4.4 versicolor
## 92           6.1          4.6 versicolor
## 93           5.8          4.0 versicolor
## 94           5.0          3.3 versicolor
## 95           5.6          4.2 versicolor
## 96           5.7          4.2 versicolor
## 97           5.7          4.2 versicolor
## 98           6.2          4.3 versicolor
## 99           5.1          3.0 versicolor
## 100          5.7          4.1 versicolor
## 101          6.3          6.0  virginica
## 102          5.8          5.1  virginica
## 103          7.1          5.9  virginica
## 104          6.3          5.6  virginica
## 105          6.5          5.8  virginica
## 106          7.6          6.6  virginica
## 107          4.9          4.5  virginica
## 108          7.3          6.3  virginica
## 109          6.7          5.8  virginica
## 110          7.2          6.1  virginica
## 111          6.5          5.1  virginica
## 112          6.4          5.3  virginica
## 113          6.8          5.5  virginica
## 114          5.7          5.0  virginica
## 115          5.8          5.1  virginica
## 116          6.4          5.3  virginica
## 117          6.5          5.5  virginica
## 118          7.7          6.7  virginica
## 119          7.7          6.9  virginica
## 120          6.0          5.0  virginica
## 121          6.9          5.7  virginica
## 122          5.6          4.9  virginica
## 123          7.7          6.7  virginica
## 124          6.3          4.9  virginica
## 125          6.7          5.7  virginica
## 126          7.2          6.0  virginica
## 127          6.2          4.8  virginica
## 128          6.1          4.9  virginica
## 129          6.4          5.6  virginica
## 130          7.2          5.8  virginica
## 131          7.4          6.1  virginica
## 132          7.9          6.4  virginica
## 133          6.4          5.6  virginica
## 134          6.3          5.1  virginica
## 135          6.1          5.6  virginica
## 136          7.7          6.1  virginica
## 137          6.3          5.6  virginica
## 138          6.4          5.5  virginica
## 139          6.0          4.8  virginica
## 140          6.9          5.4  virginica
## 141          6.7          5.6  virginica
## 142          6.9          5.1  virginica
## 143          5.8          5.1  virginica
## 144          6.8          5.9  virginica
## 145          6.7          5.7  virginica
## 146          6.7          5.2  virginica
## 147          6.3          5.0  virginica
## 148          6.5          5.2  virginica
## 149          6.2          5.4  virginica
## 150          5.9          5.1  virginica
iris[,c("Sepal.Length","Species")]
##     Sepal.Length    Species
## 1            5.1     setosa
## 2            4.9     setosa
## 3            4.7     setosa
## 4            4.6     setosa
## 5            5.0     setosa
## 6            5.4     setosa
## 7            4.6     setosa
## 8            5.0     setosa
## 9            4.4     setosa
## 10           4.9     setosa
## 11           5.4     setosa
## 12           4.8     setosa
## 13           4.8     setosa
## 14           4.3     setosa
## 15           5.8     setosa
## 16           5.7     setosa
## 17           5.4     setosa
## 18           5.1     setosa
## 19           5.7     setosa
## 20           5.1     setosa
## 21           5.4     setosa
## 22           5.1     setosa
## 23           4.6     setosa
## 24           5.1     setosa
## 25           4.8     setosa
## 26           5.0     setosa
## 27           5.0     setosa
## 28           5.2     setosa
## 29           5.2     setosa
## 30           4.7     setosa
## 31           4.8     setosa
## 32           5.4     setosa
## 33           5.2     setosa
## 34           5.5     setosa
## 35           4.9     setosa
## 36           5.0     setosa
## 37           5.5     setosa
## 38           4.9     setosa
## 39           4.4     setosa
## 40           5.1     setosa
## 41           5.0     setosa
## 42           4.5     setosa
## 43           4.4     setosa
## 44           5.0     setosa
## 45           5.1     setosa
## 46           4.8     setosa
## 47           5.1     setosa
## 48           4.6     setosa
## 49           5.3     setosa
## 50           5.0     setosa
## 51           7.0 versicolor
## 52           6.4 versicolor
## 53           6.9 versicolor
## 54           5.5 versicolor
## 55           6.5 versicolor
## 56           5.7 versicolor
## 57           6.3 versicolor
## 58           4.9 versicolor
## 59           6.6 versicolor
## 60           5.2 versicolor
## 61           5.0 versicolor
## 62           5.9 versicolor
## 63           6.0 versicolor
## 64           6.1 versicolor
## 65           5.6 versicolor
## 66           6.7 versicolor
## 67           5.6 versicolor
## 68           5.8 versicolor
## 69           6.2 versicolor
## 70           5.6 versicolor
## 71           5.9 versicolor
## 72           6.1 versicolor
## 73           6.3 versicolor
## 74           6.1 versicolor
## 75           6.4 versicolor
## 76           6.6 versicolor
## 77           6.8 versicolor
## 78           6.7 versicolor
## 79           6.0 versicolor
## 80           5.7 versicolor
## 81           5.5 versicolor
## 82           5.5 versicolor
## 83           5.8 versicolor
## 84           6.0 versicolor
## 85           5.4 versicolor
## 86           6.0 versicolor
## 87           6.7 versicolor
## 88           6.3 versicolor
## 89           5.6 versicolor
## 90           5.5 versicolor
## 91           5.5 versicolor
## 92           6.1 versicolor
## 93           5.8 versicolor
## 94           5.0 versicolor
## 95           5.6 versicolor
## 96           5.7 versicolor
## 97           5.7 versicolor
## 98           6.2 versicolor
## 99           5.1 versicolor
## 100          5.7 versicolor
## 101          6.3  virginica
## 102          5.8  virginica
## 103          7.1  virginica
## 104          6.3  virginica
## 105          6.5  virginica
## 106          7.6  virginica
## 107          4.9  virginica
## 108          7.3  virginica
## 109          6.7  virginica
## 110          7.2  virginica
## 111          6.5  virginica
## 112          6.4  virginica
## 113          6.8  virginica
## 114          5.7  virginica
## 115          5.8  virginica
## 116          6.4  virginica
## 117          6.5  virginica
## 118          7.7  virginica
## 119          7.7  virginica
## 120          6.0  virginica
## 121          6.9  virginica
## 122          5.6  virginica
## 123          7.7  virginica
## 124          6.3  virginica
## 125          6.7  virginica
## 126          7.2  virginica
## 127          6.2  virginica
## 128          6.1  virginica
## 129          6.4  virginica
## 130          7.2  virginica
## 131          7.4  virginica
## 132          7.9  virginica
## 133          6.4  virginica
## 134          6.3  virginica
## 135          6.1  virginica
## 136          7.7  virginica
## 137          6.3  virginica
## 138          6.4  virginica
## 139          6.0  virginica
## 140          6.9  virginica
## 141          6.7  virginica
## 142          6.9  virginica
## 143          5.8  virginica
## 144          6.8  virginica
## 145          6.7  virginica
## 146          6.7  virginica
## 147          6.3  virginica
## 148          6.5  virginica
## 149          6.2  virginica
## 150          5.9  virginica
iris[1:5,]
##   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
iris[1:5,c(1,3)]
##   Sepal.Length Petal.Length
## 1          5.1          1.4
## 2          4.9          1.4
## 3          4.7          1.3
## 4          4.6          1.5
## 5          5.0          1.4
iris[,-5]
##     Sepal.Length Sepal.Width Petal.Length Petal.Width
## 1            5.1         3.5          1.4         0.2
## 2            4.9         3.0          1.4         0.2
## 3            4.7         3.2          1.3         0.2
## 4            4.6         3.1          1.5         0.2
## 5            5.0         3.6          1.4         0.2
## 6            5.4         3.9          1.7         0.4
## 7            4.6         3.4          1.4         0.3
## 8            5.0         3.4          1.5         0.2
## 9            4.4         2.9          1.4         0.2
## 10           4.9         3.1          1.5         0.1
## 11           5.4         3.7          1.5         0.2
## 12           4.8         3.4          1.6         0.2
## 13           4.8         3.0          1.4         0.1
## 14           4.3         3.0          1.1         0.1
## 15           5.8         4.0          1.2         0.2
## 16           5.7         4.4          1.5         0.4
## 17           5.4         3.9          1.3         0.4
## 18           5.1         3.5          1.4         0.3
## 19           5.7         3.8          1.7         0.3
## 20           5.1         3.8          1.5         0.3
## 21           5.4         3.4          1.7         0.2
## 22           5.1         3.7          1.5         0.4
## 23           4.6         3.6          1.0         0.2
## 24           5.1         3.3          1.7         0.5
## 25           4.8         3.4          1.9         0.2
## 26           5.0         3.0          1.6         0.2
## 27           5.0         3.4          1.6         0.4
## 28           5.2         3.5          1.5         0.2
## 29           5.2         3.4          1.4         0.2
## 30           4.7         3.2          1.6         0.2
## 31           4.8         3.1          1.6         0.2
## 32           5.4         3.4          1.5         0.4
## 33           5.2         4.1          1.5         0.1
## 34           5.5         4.2          1.4         0.2
## 35           4.9         3.1          1.5         0.2
## 36           5.0         3.2          1.2         0.2
## 37           5.5         3.5          1.3         0.2
## 38           4.9         3.6          1.4         0.1
## 39           4.4         3.0          1.3         0.2
## 40           5.1         3.4          1.5         0.2
## 41           5.0         3.5          1.3         0.3
## 42           4.5         2.3          1.3         0.3
## 43           4.4         3.2          1.3         0.2
## 44           5.0         3.5          1.6         0.6
## 45           5.1         3.8          1.9         0.4
## 46           4.8         3.0          1.4         0.3
## 47           5.1         3.8          1.6         0.2
## 48           4.6         3.2          1.4         0.2
## 49           5.3         3.7          1.5         0.2
## 50           5.0         3.3          1.4         0.2
## 51           7.0         3.2          4.7         1.4
## 52           6.4         3.2          4.5         1.5
## 53           6.9         3.1          4.9         1.5
## 54           5.5         2.3          4.0         1.3
## 55           6.5         2.8          4.6         1.5
## 56           5.7         2.8          4.5         1.3
## 57           6.3         3.3          4.7         1.6
## 58           4.9         2.4          3.3         1.0
## 59           6.6         2.9          4.6         1.3
## 60           5.2         2.7          3.9         1.4
## 61           5.0         2.0          3.5         1.0
## 62           5.9         3.0          4.2         1.5
## 63           6.0         2.2          4.0         1.0
## 64           6.1         2.9          4.7         1.4
## 65           5.6         2.9          3.6         1.3
## 66           6.7         3.1          4.4         1.4
## 67           5.6         3.0          4.5         1.5
## 68           5.8         2.7          4.1         1.0
## 69           6.2         2.2          4.5         1.5
## 70           5.6         2.5          3.9         1.1
## 71           5.9         3.2          4.8         1.8
## 72           6.1         2.8          4.0         1.3
## 73           6.3         2.5          4.9         1.5
## 74           6.1         2.8          4.7         1.2
## 75           6.4         2.9          4.3         1.3
## 76           6.6         3.0          4.4         1.4
## 77           6.8         2.8          4.8         1.4
## 78           6.7         3.0          5.0         1.7
## 79           6.0         2.9          4.5         1.5
## 80           5.7         2.6          3.5         1.0
## 81           5.5         2.4          3.8         1.1
## 82           5.5         2.4          3.7         1.0
## 83           5.8         2.7          3.9         1.2
## 84           6.0         2.7          5.1         1.6
## 85           5.4         3.0          4.5         1.5
## 86           6.0         3.4          4.5         1.6
## 87           6.7         3.1          4.7         1.5
## 88           6.3         2.3          4.4         1.3
## 89           5.6         3.0          4.1         1.3
## 90           5.5         2.5          4.0         1.3
## 91           5.5         2.6          4.4         1.2
## 92           6.1         3.0          4.6         1.4
## 93           5.8         2.6          4.0         1.2
## 94           5.0         2.3          3.3         1.0
## 95           5.6         2.7          4.2         1.3
## 96           5.7         3.0          4.2         1.2
## 97           5.7         2.9          4.2         1.3
## 98           6.2         2.9          4.3         1.3
## 99           5.1         2.5          3.0         1.1
## 100          5.7         2.8          4.1         1.3
## 101          6.3         3.3          6.0         2.5
## 102          5.8         2.7          5.1         1.9
## 103          7.1         3.0          5.9         2.1
## 104          6.3         2.9          5.6         1.8
## 105          6.5         3.0          5.8         2.2
## 106          7.6         3.0          6.6         2.1
## 107          4.9         2.5          4.5         1.7
## 108          7.3         2.9          6.3         1.8
## 109          6.7         2.5          5.8         1.8
## 110          7.2         3.6          6.1         2.5
## 111          6.5         3.2          5.1         2.0
## 112          6.4         2.7          5.3         1.9
## 113          6.8         3.0          5.5         2.1
## 114          5.7         2.5          5.0         2.0
## 115          5.8         2.8          5.1         2.4
## 116          6.4         3.2          5.3         2.3
## 117          6.5         3.0          5.5         1.8
## 118          7.7         3.8          6.7         2.2
## 119          7.7         2.6          6.9         2.3
## 120          6.0         2.2          5.0         1.5
## 121          6.9         3.2          5.7         2.3
## 122          5.6         2.8          4.9         2.0
## 123          7.7         2.8          6.7         2.0
## 124          6.3         2.7          4.9         1.8
## 125          6.7         3.3          5.7         2.1
## 126          7.2         3.2          6.0         1.8
## 127          6.2         2.8          4.8         1.8
## 128          6.1         3.0          4.9         1.8
## 129          6.4         2.8          5.6         2.1
## 130          7.2         3.0          5.8         1.6
## 131          7.4         2.8          6.1         1.9
## 132          7.9         3.8          6.4         2.0
## 133          6.4         2.8          5.6         2.2
## 134          6.3         2.8          5.1         1.5
## 135          6.1         2.6          5.6         1.4
## 136          7.7         3.0          6.1         2.3
## 137          6.3         3.4          5.6         2.4
## 138          6.4         3.1          5.5         1.8
## 139          6.0         3.0          4.8         1.8
## 140          6.9         3.1          5.4         2.1
## 141          6.7         3.1          5.6         2.4
## 142          6.9         3.1          5.1         2.3
## 143          5.8         2.7          5.1         1.9
## 144          6.8         3.2          5.9         2.3
## 145          6.7         3.3          5.7         2.5
## 146          6.7         3.0          5.2         2.3
## 147          6.3         2.5          5.0         1.9
## 148          6.5         3.0          5.2         2.0
## 149          6.2         3.4          5.4         2.3
## 150          5.9         3.0          5.1         1.8
iris$Species
##   [1] setosa     setosa     setosa     setosa     setosa     setosa    
##   [7] setosa     setosa     setosa     setosa     setosa     setosa    
##  [13] setosa     setosa     setosa     setosa     setosa     setosa    
##  [19] setosa     setosa     setosa     setosa     setosa     setosa    
##  [25] setosa     setosa     setosa     setosa     setosa     setosa    
##  [31] setosa     setosa     setosa     setosa     setosa     setosa    
##  [37] setosa     setosa     setosa     setosa     setosa     setosa    
##  [43] setosa     setosa     setosa     setosa     setosa     setosa    
##  [49] setosa     setosa     versicolor versicolor versicolor versicolor
##  [55] versicolor versicolor versicolor versicolor versicolor versicolor
##  [61] versicolor versicolor versicolor versicolor versicolor versicolor
##  [67] versicolor versicolor versicolor versicolor versicolor versicolor
##  [73] versicolor versicolor versicolor versicolor versicolor versicolor
##  [79] versicolor versicolor versicolor versicolor versicolor versicolor
##  [85] versicolor versicolor versicolor versicolor versicolor versicolor
##  [91] versicolor versicolor versicolor versicolor versicolor versicolor
##  [97] versicolor versicolor versicolor versicolor virginica  virginica 
## [103] virginica  virginica  virginica  virginica  virginica  virginica 
## [109] virginica  virginica  virginica  virginica  virginica  virginica 
## [115] virginica  virginica  virginica  virginica  virginica  virginica 
## [121] virginica  virginica  virginica  virginica  virginica  virginica 
## [127] virginica  virginica  virginica  virginica  virginica  virginica 
## [133] virginica  virginica  virginica  virginica  virginica  virginica 
## [139] virginica  virginica  virginica  virginica  virginica  virginica 
## [145] virginica  virginica  virginica  virginica  virginica  virginica 
## Levels: setosa versicolor virginica
as.integer(3.14)
## [1] 3
as.numeric(FALSE)
## [1] 0
as.logical(0.0001)
## [1] TRUE
getwd()
## [1] "C:/Users/강원지부 검사/Desktop/R"
setwd("c:/data")
getwd()
## [1] "c:/data"
#data<-read.csv("c:/data/Data1.csv")
data<-read.csv("Data1.csv", header=TRUE, sep=",")
data[1:5,]
##   X Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 Q19 Q20
## 1 1  4  4  2  3  4  2  2  4  4   4   4   4   4   4   4   4   4   4   4   4
## 2 2  4  4  4  4  4  3  2  4  4   4   4   4   4   4   4   4   3   4   2   1
## 3 3  4  4  4  4  2  4  4  4  4   2   4   4   4   4   3   4   4   4   4   3
## 4 4  5  4  4  4  4  4  4  4  4   4   4   4   4   4   4   4   4   4   4   4
## 5 5  4  4  4  4  4  4  4  4  2   4   4   4   4   4   4   4   4   4   4   4
##   Gender EDU  BF  BM Happiness Peace
## 1      0   1 3.4 3.2       4.0   4.0
## 2      0   1 4.0 3.4       4.0   2.8
## 3      0   2 3.6 3.6       3.8   3.8
## 4      0   1 4.2 4.0       4.0   4.0
## 5      0   2 4.0 3.6       4.0   4.0
names(data)
##  [1] "X"         "Q1"        "Q2"        "Q3"        "Q4"        "Q5"       
##  [7] "Q6"        "Q7"        "Q8"        "Q9"        "Q10"       "Q11"      
## [13] "Q12"       "Q13"       "Q14"       "Q15"       "Q16"       "Q17"      
## [19] "Q18"       "Q19"       "Q20"       "Gender"    "EDU"       "BF"       
## [25] "BM"        "Happiness" "Peace"
library(readxl)
data1<-read_excel("Data1.xls")
head(data1);tail(data1)
## # A tibble: 6 × 26
##      Q1    Q2    Q3    Q4    Q5    Q6    Q7    Q8    Q9   Q10   Q11   Q12   Q13
##   <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1     4     4     2     3     4     2     2     4     4     4     4     4     4
## 2     4     4     4     4     4     3     2     4     4     4     4     4     4
## 3     4     4     4     4     2     4     4     4     4     2     4     4     4
## 4     5     4     4     4     4     4     4     4     4     4     4     4     4
## 5     4     4     4     4     4     4     4     4     2     4     4     4     4
## 6     4     4     4     4     4     4     4     4     4     4     4     4     4
## # ℹ 13 more variables: Q14 <dbl>, Q15 <dbl>, Q16 <dbl>, Q17 <dbl>, Q18 <dbl>,
## #   Q19 <dbl>, Q20 <dbl>, Gender <dbl>, EDU <dbl>, BF <dbl>, BM <dbl>,
## #   Happiness <dbl>, Peace <dbl>
## # A tibble: 6 × 26
##      Q1    Q2    Q3    Q4    Q5    Q6    Q7    Q8    Q9   Q10   Q11   Q12   Q13
##   <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
## 1     4     4     3     4     4     2     2     3     4     2     2     4     3
## 2     2     2     2     1     2     2     2     2     2     2     1     3     2
## 3     3     2     2     2     3     1     1     1     1     1     3     3     3
## 4     5     4     4     4     4     2     2     2     2     3     3     4     3
## 5     4     4     4     2     2     4     2     4     4     3     3     2     3
## 6     3     3     1     1     2     1     1     1     1     1     4     4     3
## # ℹ 13 more variables: Q14 <dbl>, Q15 <dbl>, Q16 <dbl>, Q17 <dbl>, Q18 <dbl>,
## #   Q19 <dbl>, Q20 <dbl>, Gender <dbl>, EDU <dbl>, BF <dbl>, BM <dbl>,
## #   Happiness <dbl>, Peace <dbl>
data2<-read.table("Data1.txt",header=TRUE)
head(data2)
##   Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 Q19 Q20 Gender
## 1  4  4  2  3  4  2  2  4  4   4   4   4   4   4   4   4   4   4   4   4      0
## 2  4  4  4  4  4  3  2  4  4   4   4   4   4   4   4   4   3   4   2   1      0
## 3  4  4  4  4  2  4  4  4  4   2   4   4   4   4   3   4   4   4   4   3      0
## 4  5  4  4  4  4  4  4  4  4   4   4   4   4   4   4   4   4   4   4   4      0
## 5  4  4  4  4  4  4  4  4  2   4   4   4   4   4   4   4   4   4   4   4      0
## 6  4  4  4  4  4  4  4  4  4   4   4   4   4   4   4   4   4   4   4   4      0
##   EDU  BF  BM Happiness Peace
## 1   1 3.4 3.2       4.0   4.0
## 2   1 4.0 3.4       4.0   2.8
## 3   2 3.6 3.6       3.8   3.8
## 4   1 4.2 4.0       4.0   4.0
## 5   2 4.0 3.6       4.0   4.0
## 6   1 4.0 4.0       4.0   4.0
data(mtcars)
write.csv(mtcars,file="mtcars.csv")

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
head(iris,3)
##   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
tail(iris)
##     Sepal.Length Sepal.Width Petal.Length Petal.Width   Species
## 145          6.7         3.3          5.7         2.5 virginica
## 146          6.7         3.0          5.2         2.3 virginica
## 147          6.3         2.5          5.0         1.9 virginica
## 148          6.5         3.0          5.2         2.0 virginica
## 149          6.2         3.4          5.4         2.3 virginica
## 150          5.9         3.0          5.1         1.8 virginica
str(iris)
## 'data.frame':    150 obs. of  5 variables:
##  $ Sepal.Length: num  5.1 4.9 4.7 4.6 5 5.4 4.6 5 4.4 4.9 ...
##  $ Sepal.Width : num  3.5 3 3.2 3.1 3.6 3.9 3.4 3.4 2.9 3.1 ...
##  $ Petal.Length: num  1.4 1.4 1.3 1.5 1.4 1.7 1.4 1.5 1.4 1.5 ...
##  $ Petal.Width : num  0.2 0.2 0.2 0.2 0.2 0.4 0.3 0.2 0.2 0.1 ...
##  $ Species     : Factor w/ 3 levels "setosa","versicolor",..: 1 1 1 1 1 1 1 1 1 1 ...
glimpse(iris)
## Rows: 150
## Columns: 5
## $ Sepal.Length <dbl> 5.1, 4.9, 4.7, 4.6, 5.0, 5.4, 4.6, 5.0, 4.4, 4.9, 5.4, 4.…
## $ Sepal.Width  <dbl> 3.5, 3.0, 3.2, 3.1, 3.6, 3.9, 3.4, 3.4, 2.9, 3.1, 3.7, 3.…
## $ Petal.Length <dbl> 1.4, 1.4, 1.3, 1.5, 1.4, 1.7, 1.4, 1.5, 1.4, 1.5, 1.5, 1.…
## $ Petal.Width  <dbl> 0.2, 0.2, 0.2, 0.2, 0.2, 0.4, 0.3, 0.2, 0.2, 0.1, 0.2, 0.…
## $ Species      <fct> setosa, setosa, setosa, setosa, setosa, setosa, setosa, s…
View(iris)
dim(iris)
## [1] 150   5
ls(iris)
## [1] "Petal.Length" "Petal.Width"  "Sepal.Length" "Sepal.Width"  "Species"
ls()
##  [1] "a"         "bloodtype" "car"       "data"      "data1"     "data2"    
##  [7] "df"        "df2"       "gender"    "height"    "iris"      "mtcars"   
## [13] "weight"    "x"         "xy"        "y"
rm(list=ls())
ls()
## character(0)
mean(mtcars$mpg)
## [1] 20.09062
var(mtcars$mpg)
## [1] 36.3241
sd(mtcars$mpg)
## [1] 6.026948
sum(mtcars$mpg)
## [1] 642.9
range(mtcars$mpg)
## [1] 10.4 33.9
max(mtcars$mpg)
## [1] 33.9
min(mtcars$mpg)
## [1] 10.4
quantile(mtcars$mpg)
##     0%    25%    50%    75%   100% 
## 10.400 15.425 19.200 22.800 33.900
IQR(mtcars$mpg)
## [1] 7.375
IQR(mtcars$mpg)
## [1] 7.375
summary(mtcars)
##       mpg             cyl             disp             hp       
##  Min.   :10.40   Min.   :4.000   Min.   : 71.1   Min.   : 52.0  
##  1st Qu.:15.43   1st Qu.:4.000   1st Qu.:120.8   1st Qu.: 96.5  
##  Median :19.20   Median :6.000   Median :196.3   Median :123.0  
##  Mean   :20.09   Mean   :6.188   Mean   :230.7   Mean   :146.7  
##  3rd Qu.:22.80   3rd Qu.:8.000   3rd Qu.:326.0   3rd Qu.:180.0  
##  Max.   :33.90   Max.   :8.000   Max.   :472.0   Max.   :335.0  
##       drat             wt             qsec             vs        
##  Min.   :2.760   Min.   :1.513   Min.   :14.50   Min.   :0.0000  
##  1st Qu.:3.080   1st Qu.:2.581   1st Qu.:16.89   1st Qu.:0.0000  
##  Median :3.695   Median :3.325   Median :17.71   Median :0.0000  
##  Mean   :3.597   Mean   :3.217   Mean   :17.85   Mean   :0.4375  
##  3rd Qu.:3.920   3rd Qu.:3.610   3rd Qu.:18.90   3rd Qu.:1.0000  
##  Max.   :4.930   Max.   :5.424   Max.   :22.90   Max.   :1.0000  
##        am              gear            carb      
##  Min.   :0.0000   Min.   :3.000   Min.   :1.000  
##  1st Qu.:0.0000   1st Qu.:3.000   1st Qu.:2.000  
##  Median :0.0000   Median :4.000   Median :2.000  
##  Mean   :0.4062   Mean   :3.688   Mean   :2.812  
##  3rd Qu.:1.0000   3rd Qu.:4.000   3rd Qu.:4.000  
##  Max.   :1.0000   Max.   :5.000   Max.   :8.000
df<-read.csv("Data1.csv")
glimpse(df)
## Rows: 1,925
## Columns: 27
## $ X         <int> 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 1…
## $ Q1        <int> 4, 4, 4, 5, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, …
## $ Q2        <int> 4, 4, 4, 4, 4, 4, 2, 2, 4, 4, 4, 4, 4, 2, 4, 4, 2, 4, 2, 2, …
## $ Q3        <int> 2, 4, 4, 4, 4, 4, 4, 4, 4, 2, 4, 2, 4, 4, 4, 4, 4, 3, 2, 3, …
## $ Q4        <int> 3, 4, 4, 4, 4, 4, 4, 4, 4, 2, 4, 4, 4, 2, 4, 4, 4, 2, 2, 4, …
## $ Q5        <int> 4, 4, 2, 4, 4, 4, 4, 4, 2, 4, 4, 2, 4, 4, 4, 4, 4, 3, 1, 2, …
## $ Q6        <int> 2, 3, 4, 4, 4, 4, 4, 4, 1, 2, 2, 2, 4, 4, 3, 5, 2, 2, 1, 4, …
## $ Q7        <int> 2, 2, 4, 4, 4, 4, 4, 4, 3, 4, 4, 4, 5, 4, 4, 5, 4, 3, 4, 4, …
## $ Q8        <int> 4, 4, 4, 4, 4, 4, 5, 5, 2, 2, 4, 4, 4, 4, 3, 5, 4, 2, 4, 4, …
## $ Q9        <int> 4, 4, 4, 4, 2, 4, 5, 5, 3, 4, 4, 4, 2, 2, 4, 5, 2, 4, 2, 4, …
## $ Q10       <int> 4, 4, 2, 4, 4, 4, 5, 5, 2, 4, 2, 4, 4, 4, 3, 4, 4, 3, 2, 3, …
## $ Q11       <int> 4, 4, 4, 4, 4, 4, 5, 5, 4, 4, 4, 3, 4, 4, 4, 4, 5, 4, 3, 3, …
## $ Q12       <int> 4, 4, 4, 4, 4, 4, 5, 5, 3, 4, 4, 3, 4, 3, 3, 4, 5, 4, 4, 2, …
## $ Q13       <int> 4, 4, 4, 4, 4, 4, 5, 5, 4, 4, 4, 4, 2, 4, 4, 4, 5, 4, 4, 4, …
## $ Q14       <int> 4, 4, 4, 4, 4, 4, 5, 5, 5, 4, 4, 4, 3, 4, 5, 4, 5, 4, 4, 4, …
## $ Q15       <int> 4, 4, 3, 4, 4, 4, 4, 2, 3, 4, 4, 3, 1, 4, 4, 4, 5, 4, 4, 4, …
## $ Q16       <int> 4, 4, 4, 4, 4, 4, 5, 2, 4, 4, 4, 4, 4, 4, 5, 4, 5, 4, 4, 4, …
## $ Q17       <int> 4, 3, 4, 4, 4, 4, 2, 2, 4, 4, 4, 4, 3, 2, 4, 5, 4, 4, 3, 4, …
## $ Q18       <int> 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 2, 4, 4, 4, …
## $ Q19       <int> 4, 2, 4, 4, 4, 4, 4, 2, 4, 2, 4, 4, 1, 4, 4, 4, 5, 4, 2, 3, …
## $ Q20       <int> 4, 1, 3, 4, 4, 4, 4, 2, 4, 2, 4, 4, 4, 2, 4, 5, 5, 4, 2, 4, …
## $ Gender    <int> 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0, …
## $ EDU       <int> 1, 1, 2, 1, 2, 1, 1, 1, 4, 3, 2, 1, 1, 3, 3, 2, 1, 1, 1, 4, …
## $ BF        <dbl> 3.4, 4.0, 3.6, 4.2, 4.0, 4.0, 3.6, 3.6, 3.6, 3.2, 4.0, 3.2, …
## $ BM        <dbl> 3.2, 3.4, 3.6, 4.0, 3.6, 4.0, 4.6, 4.6, 2.2, 3.2, 3.2, 3.6, …
## $ Happiness <dbl> 4.0, 4.0, 3.8, 4.0, 4.0, 4.0, 4.8, 4.4, 3.8, 4.0, 4.0, 3.4, …
## $ Peace     <dbl> 4.0, 2.8, 3.8, 4.0, 4.0, 4.0, 3.8, 2.4, 4.0, 3.2, 4.0, 3.9, …
df$Gender<-factor(df$Gender)

library(ggplot2)
data("diamonds")
glimpse(diamonds)
## Rows: 53,940
## Columns: 10
## $ carat   <dbl> 0.23, 0.21, 0.23, 0.29, 0.31, 0.24, 0.24, 0.26, 0.22, 0.23, 0.…
## $ cut     <ord> Ideal, Premium, Good, Premium, Good, Very Good, Very Good, Ver…
## $ color   <ord> E, E, E, I, J, J, I, H, E, H, J, J, F, J, E, E, I, J, J, J, I,…
## $ clarity <ord> SI2, SI1, VS1, VS2, SI2, VVS2, VVS1, SI1, VS2, VS1, SI1, VS1, …
## $ depth   <dbl> 61.5, 59.8, 56.9, 62.4, 63.3, 62.8, 62.3, 61.9, 65.1, 59.4, 64…
## $ table   <dbl> 55, 61, 65, 58, 58, 57, 57, 55, 61, 61, 55, 56, 61, 54, 62, 58…
## $ price   <int> 326, 326, 327, 334, 335, 336, 336, 337, 337, 338, 339, 340, 34…
## $ x       <dbl> 3.95, 3.89, 4.05, 4.20, 4.34, 3.94, 3.95, 4.07, 3.87, 4.00, 4.…
## $ y       <dbl> 3.98, 3.84, 4.07, 4.23, 4.35, 3.96, 3.98, 4.11, 3.78, 4.05, 4.…
## $ z       <dbl> 2.43, 2.31, 2.31, 2.63, 2.75, 2.48, 2.47, 2.53, 2.49, 2.39, 2.…
diamonds1<-diamonds %>% rename(c=clarity, p=price)
glimpse(diamonds1)
## Rows: 53,940
## Columns: 10
## $ carat <dbl> 0.23, 0.21, 0.23, 0.29, 0.31, 0.24, 0.24, 0.26, 0.22, 0.23, 0.30…
## $ cut   <ord> Ideal, Premium, Good, Premium, Good, Very Good, Very Good, Very …
## $ color <ord> E, E, E, I, J, J, I, H, E, H, J, J, F, J, E, E, I, J, J, J, I, E…
## $ c     <ord> SI2, SI1, VS1, VS2, SI2, VVS2, VVS1, SI1, VS2, VS1, SI1, VS1, SI…
## $ depth <dbl> 61.5, 59.8, 56.9, 62.4, 63.3, 62.8, 62.3, 61.9, 65.1, 59.4, 64.0…
## $ table <dbl> 55, 61, 65, 58, 58, 57, 57, 55, 61, 61, 55, 56, 61, 54, 62, 58, …
## $ p     <int> 326, 326, 327, 334, 335, 336, 336, 337, 337, 338, 339, 340, 342,…
## $ x     <dbl> 3.95, 3.89, 4.05, 4.20, 4.34, 3.94, 3.95, 4.07, 3.87, 4.00, 4.25…
## $ y     <dbl> 3.98, 3.84, 4.07, 4.23, 4.35, 3.96, 3.98, 4.11, 3.78, 4.05, 4.28…
## $ z     <dbl> 2.43, 2.31, 2.31, 2.63, 2.75, 2.48, 2.47, 2.53, 2.49, 2.39, 2.73…
diamonds %>% head %>% dim #== dim(head(diamonds))
## [1]  6 10
count(diamonds1,cut)
## # A tibble: 5 × 2
##   cut           n
##   <ord>     <int>
## 1 Fair       1610
## 2 Good       4906
## 3 Very Good 12082
## 4 Premium   13791
## 5 Ideal     21551
count(diamonds1,c)
## # A tibble: 8 × 2
##   c         n
##   <ord> <int>
## 1 I1      741
## 2 SI2    9194
## 3 SI1   13065
## 4 VS2   12258
## 5 VS1    8171
## 6 VVS2   5066
## 7 VVS1   3655
## 8 IF     1790
df1<-diamonds %>% select(carat,price)
head(df1,3)
## # A tibble: 3 × 2
##   carat price
##   <dbl> <int>
## 1  0.23   326
## 2  0.21   326
## 3  0.23   327
df2<-diamonds %>% select(-carat,-price)
head(df2,3)
## # A tibble: 3 × 8
##   cut     color clarity depth table     x     y     z
##   <ord>   <ord> <ord>   <dbl> <dbl> <dbl> <dbl> <dbl>
## 1 Ideal   E     SI2      61.5    55  3.95  3.98  2.43
## 2 Premium E     SI1      59.8    61  3.89  3.84  2.31
## 3 Good    E     VS1      56.9    65  4.05  4.07  2.31
df2<-diamonds %>% select(-1,-4)
head(df2,3)
## # A tibble: 3 × 8
##   cut     color depth table price     x     y     z
##   <ord>   <ord> <dbl> <dbl> <int> <dbl> <dbl> <dbl>
## 1 Ideal   E      61.5    55   326  3.95  3.98  2.43
## 2 Premium E      59.8    61   326  3.89  3.84  2.31
## 3 Good    E      56.9    65   327  4.05  4.07  2.31
df2<-diamonds %>% select(1,3,5)
head(df2,3)
## # A tibble: 3 × 3
##   carat color depth
##   <dbl> <ord> <dbl>
## 1  0.23 E      61.5
## 2  0.21 E      59.8
## 3  0.23 E      56.9
df2<-diamonds %>% slice(2)
head(df2,3)
## # A tibble: 1 × 10
##   carat cut     color clarity depth table price     x     y     z
##   <dbl> <ord>   <ord> <ord>   <dbl> <dbl> <int> <dbl> <dbl> <dbl>
## 1  0.21 Premium E     SI1      59.8    61   326  3.89  3.84  2.31
df2<-diamonds %>% filter(cut=="Good")
head(df2,3)
## # A tibble: 3 × 10
##   carat cut   color clarity depth table price     x     y     z
##   <dbl> <ord> <ord> <ord>   <dbl> <dbl> <int> <dbl> <dbl> <dbl>
## 1  0.23 Good  E     VS1      56.9    65   327  4.05  4.07  2.31
## 2  0.31 Good  J     SI2      63.3    58   335  4.34  4.35  2.75
## 3  0.3  Good  J     SI1      64      55   339  4.25  4.28  2.73
d_max<-max(diamonds$price)
diamonds %>% filter(price==d_max)
## # A tibble: 1 × 10
##   carat cut     color clarity depth table price     x     y     z
##   <dbl> <ord>   <ord> <ord>   <dbl> <dbl> <int> <dbl> <dbl> <dbl>
## 1  2.29 Premium I     VS2      60.8    60 18823   8.5  8.47  5.16
diamonds %>% filter(cut!="Premium") %>% head(3)
## # A tibble: 3 × 10
##   carat cut   color clarity depth table price     x     y     z
##   <dbl> <ord> <ord> <ord>   <dbl> <dbl> <int> <dbl> <dbl> <dbl>
## 1  0.23 Ideal E     SI2      61.5    55   326  3.95  3.98  2.43
## 2  0.23 Good  E     VS1      56.9    65   327  4.05  4.07  2.31
## 3  0.31 Good  J     SI2      63.3    58   335  4.34  4.35  2.75
diamonds %>% filter(price>=1000) %>% head(3)
## # A tibble: 3 × 10
##   carat cut   color clarity depth table price     x     y     z
##   <dbl> <ord> <ord> <ord>   <dbl> <dbl> <int> <dbl> <dbl> <dbl>
## 1  0.7  Ideal E     SI1      62.5    57  2757  5.7   5.72  3.57
## 2  0.86 Fair  E     SI2      55.1    69  2757  6.45  6.33  3.52
## 3  0.7  Ideal G     VS2      61.6    56  2757  5.7   5.67  3.5
diamonds %>% filter(price!=1000) %>% head(3)
## # A tibble: 3 × 10
##   carat cut     color clarity depth table price     x     y     z
##   <dbl> <ord>   <ord> <ord>   <dbl> <dbl> <int> <dbl> <dbl> <dbl>
## 1  0.23 Ideal   E     SI2      61.5    55   326  3.95  3.98  2.43
## 2  0.21 Premium E     SI1      59.8    61   326  3.89  3.84  2.31
## 3  0.23 Good    E     VS1      56.9    65   327  4.05  4.07  2.31
diamonds %>% filter(price!=1000 & cut=="Ideal" & color=="E") %>% head(3)
## # A tibble: 3 × 10
##   carat cut   color clarity depth table price     x     y     z
##   <dbl> <ord> <ord> <ord>   <dbl> <dbl> <int> <dbl> <dbl> <dbl>
## 1  0.23 Ideal E     SI2      61.5    55   326  3.95  3.98  2.43
## 2  0.26 Ideal E     VVS2     62.9    58   554  4.02  4.06  2.54
## 3  0.7  Ideal E     SI1      62.5    57  2757  5.7   5.72  3.57
diamonds %>% filter(carat<1 | carat>0.5) %>% head(3)
## # A tibble: 3 × 10
##   carat cut     color clarity depth table price     x     y     z
##   <dbl> <ord>   <ord> <ord>   <dbl> <dbl> <int> <dbl> <dbl> <dbl>
## 1  0.23 Ideal   E     SI2      61.5    55   326  3.95  3.98  2.43
## 2  0.21 Premium E     SI1      59.8    61   326  3.89  3.84  2.31
## 3  0.23 Good    E     VS1      56.9    65   327  4.05  4.07  2.31
diamonds %>% filter(cut%in%c("Ideal","Good")) %>% head(3)
## # A tibble: 3 × 10
##   carat cut   color clarity depth table price     x     y     z
##   <dbl> <ord> <ord> <ord>   <dbl> <dbl> <int> <dbl> <dbl> <dbl>
## 1  0.23 Ideal E     SI2      61.5    55   326  3.95  3.98  2.43
## 2  0.23 Good  E     VS1      56.9    65   327  4.05  4.07  2.31
## 3  0.31 Good  J     SI2      63.3    58   335  4.34  4.35  2.75
diamonds %>% select(carat,depth,price) %>% 
  filter(depth==max(depth)|price==min(price))
## # A tibble: 4 × 3
##   carat depth price
##   <dbl> <dbl> <int>
## 1  0.23  61.5   326
## 2  0.21  59.8   326
## 3  0.5   79    2579
## 4  0.5   79    2579
diamonds %>% mutate(Ratio=price/carat,Double=Ratio*2) %>% head(3)
## # A tibble: 3 × 12
##   carat cut     color clarity depth table price     x     y     z Ratio Double
##   <dbl> <ord>   <ord> <ord>   <dbl> <dbl> <int> <dbl> <dbl> <dbl> <dbl>  <dbl>
## 1  0.23 Ideal   E     SI2      61.5    55   326  3.95  3.98  2.43 1417.  2835.
## 2  0.21 Premium E     SI1      59.8    61   326  3.89  3.84  2.31 1552.  3105.
## 3  0.23 Good    E     VS1      56.9    65   327  4.05  4.07  2.31 1422.  2843.
diamonds %>% summarise(AvgPrice=mean(price),
MedianPrice=median(price),
AvgCarat=mean(carat))
## # A tibble: 1 × 3
##   AvgPrice MedianPrice AvgCarat
##      <dbl>       <dbl>    <dbl>
## 1    3933.        2401    0.798
diamonds %>% group_by(cut) %>%
  summarize(AvgPrice=mean(price),SumCarat=sum(carat))
## # A tibble: 5 × 3
##   cut       AvgPrice SumCarat
##   <ord>        <dbl>    <dbl>
## 1 Fair         4359.    1684.
## 2 Good         3929.    4166.
## 3 Very Good    3982.    9743.
## 4 Premium      4584.   12301.
## 5 Ideal        3458.   15147.
diamonds %>% group_by(cut) %>%
  summarize(n=n()) %>%
  mutate(total=sum(n), pct=n/total*100)
## # A tibble: 5 × 4
##   cut           n total   pct
##   <ord>     <int> <int> <dbl>
## 1 Fair       1610 53940  2.98
## 2 Good       4906 53940  9.10
## 3 Very Good 12082 53940 22.4 
## 4 Premium   13791 53940 25.6 
## 5 Ideal     21551 53940 40.0
quantile(diamonds$price)
##       0%      25%      50%      75%     100% 
##   326.00   950.00  2401.00  5324.25 18823.00
diamonds1<-diamonds %>% 
  mutate(price_class=ifelse(price>=5324.25,"best",
                     ifelse(price<=2401,"good",
                     ifelse(price>=950,"normal","bad"))))
table(diamonds1$price_class)
## 
##   best   good normal 
##  13485  26985  13470
diamonds %>% group_by(cut) %>%
  summarise(AvgPrice=mean(price)) %>%
  arrange(desc(AvgPrice))
## # A tibble: 5 × 2
##   cut       AvgPrice
##   <ord>        <dbl>
## 1 Premium      4584.
## 2 Fair         4359.
## 3 Very Good    3982.
## 4 Good         3929.
## 5 Ideal        3458.
data("airquality")
summary(airquality)
##      Ozone           Solar.R           Wind             Temp      
##  Min.   :  1.00   Min.   :  7.0   Min.   : 1.700   Min.   :56.00  
##  1st Qu.: 18.00   1st Qu.:115.8   1st Qu.: 7.400   1st Qu.:72.00  
##  Median : 31.50   Median :205.0   Median : 9.700   Median :79.00  
##  Mean   : 42.13   Mean   :185.9   Mean   : 9.958   Mean   :77.88  
##  3rd Qu.: 63.25   3rd Qu.:258.8   3rd Qu.:11.500   3rd Qu.:85.00  
##  Max.   :168.00   Max.   :334.0   Max.   :20.700   Max.   :97.00  
##  NA's   :37       NA's   :7                                       
##      Month            Day      
##  Min.   :5.000   Min.   : 1.0  
##  1st Qu.:6.000   1st Qu.: 8.0  
##  Median :7.000   Median :16.0  
##  Mean   :6.993   Mean   :15.8  
##  3rd Qu.:8.000   3rd Qu.:23.0  
##  Max.   :9.000   Max.   :31.0  
## 
View(airquality)

names(airquality)<-tolower(names(airquality))
is.na(airquality$ozone)
##   [1] FALSE FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE  TRUE FALSE FALSE
##  [13] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
##  [25]  TRUE  TRUE  TRUE FALSE FALSE FALSE FALSE  TRUE  TRUE  TRUE  TRUE  TRUE
##  [37]  TRUE FALSE  TRUE FALSE FALSE  TRUE  TRUE FALSE  TRUE  TRUE FALSE FALSE
##  [49] FALSE FALSE FALSE  TRUE  TRUE  TRUE  TRUE  TRUE  TRUE  TRUE  TRUE  TRUE
##  [61]  TRUE FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE
##  [73] FALSE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE  TRUE
##  [85] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
##  [97] FALSE FALSE FALSE FALSE FALSE  TRUE  TRUE FALSE FALSE FALSE  TRUE FALSE
## [109] FALSE FALSE FALSE FALSE FALSE FALSE  TRUE FALSE FALSE FALSE  TRUE FALSE
## [121] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [133] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [145] FALSE FALSE FALSE FALSE FALSE  TRUE FALSE FALSE FALSE
table(is.na(airquality))
## 
## FALSE  TRUE 
##   874    44
table(is.na(airquality$ozone))
## 
## FALSE  TRUE 
##   116    37
summary(is.na(airquality))
##    ozone          solar.r           wind            temp        
##  Mode :logical   Mode :logical   Mode :logical   Mode :logical  
##  FALSE:116       FALSE:146       FALSE:153       FALSE:153      
##  TRUE :37        TRUE :7                                        
##    month            day         
##  Mode :logical   Mode :logical  
##  FALSE:153       FALSE:153      
## 
sum(airquality$ozone)
## [1] NA
mean(airquality$ozone)
## [1] NA
sum(airquality$ozone,na.rm=TRUE)
## [1] 4887
mean(airquality$ozone,na.rm=TRUE)
## [1] 42.12931
airquality<-na.omit(airquality)
table(is.na(airquality))
## 
## FALSE 
##   666
airquality %>% filter(!is.na(ozone)) %>% head(3)
##   ozone solar.r wind temp month day
## 1    41     190  7.4   67     5   1
## 2    36     118  8.0   72     5   2
## 3    12     149 12.6   74     5   3
airquality %>% filter(!is.na(ozone)&!is.na(solar.r)) %>% head(3)
##   ozone solar.r wind temp month day
## 1    41     190  7.4   67     5   1
## 2    36     118  8.0   72     5   2
## 3    12     149 12.6   74     5   3
mean <- mean(airquality$ozone,na.rm=TRUE)
airquality$ozone <- ifelse(is.na(airquality$ozone),mean,airquality$ozone)
table(airquality$ozone)
## 
##   1   4   6   7   8   9  10  11  12  13  14  16  18  19  20  21  22  23  24  27 
##   1   1   1   2   1   3   1   3   2   4   4   4   4   1   4   4   1   6   2   1 
##  28  29  30  31  32  34  35  36  37  39  40  41  44  45  46  47  48  49  50  52 
##   2   1   2   1   3   1   1   2   2   2   1   1   3   2   1   1   1   1   1   1 
##  59  61  63  64  65  71  73  76  77  78  79  80  82  84  85  89  91  96  97 108 
##   2   1   1   2   1   1   2   1   1   1   1   1   1   1   2   1   1   1   2   1 
## 110 115 118 122 135 168 
##   1   1   1   1   1   1
ott7 <- data.frame(gender=c("1","1","2","2","2","3"),
                   income=c(200,250,200,300,200,150))
ott7
##   gender income
## 1      1    200
## 2      1    250
## 3      2    200
## 4      2    300
## 5      2    200
## 6      3    150
boxplot(iris$Sepal.Width)$stats

##      [,1]
## [1,]  2.2
## [2,]  2.8
## [3,]  3.0
## [4,]  3.3
## [5,]  4.0
iris %>% filter(Sepal.Width>4.0|Sepal.Width<2.2)
##   Sepal.Length Sepal.Width Petal.Length Petal.Width    Species
## 1          5.7         4.4          1.5         0.4     setosa
## 2          5.2         4.1          1.5         0.1     setosa
## 3          5.5         4.2          1.4         0.2     setosa
## 4          5.0         2.0          3.5         1.0 versicolor
iris$Sepal.Width <- ifelse(iris$Sepal.Width>4.0 | iris$Sepal.Width<2.2,
                           NA, iris$Sepal.Width)
table(is.na(iris$Sepal.Width))
## 
## FALSE  TRUE 
##   146     4
iris %>% filter(!is.na(Sepal.Width)) %>% dim
## [1] 146   5
library(readxl)
airseoul<-read_excel("period1.xlsx")

names(airseoul)
## [1] "날짜"                        "측정소명"                   
## [3] "미세먼지 PM10\r\n(㎍/m3)"    "초미세먼지\r\nPM2.5 (㎍/m3)"
## [5] "오존\r\nO3 (ppm)"            "이산화질소\r\nNO2 (ppm)"    
## [7] "일산화탄소\r\nCO (ppm)"      "아황산가스\r\nSO2(ppm)"
airseoul1 <- airseoul %>% rename(date="날짜", region="측정소명", 
                               pm10="미세먼지 PM10\r\n(㎍/m3)",
                               pm2.5="초미세먼지\r\nPM2.5 (㎍/m3)") %>% 
                          select(date,region,pm10,pm2.5)

table(airseoul1$date)
## 
## 2022-02-01 2022-02-02 2022-02-03 2022-02-04 2022-02-05 2022-02-06 2022-02-07 
##         26         26         26         26         26         26         26 
## 2022-02-08 2022-02-09 2022-02-10 2022-02-11 2022-02-12 2022-02-13 2022-02-14 
##         26         26         26         26         26         26         26 
## 2022-02-15 2022-02-16 2022-02-17 2022-02-18 2022-02-19 2022-02-20 2022-02-21 
##         26         26         26         26         26         26         26 
## 2022-02-22 2022-02-23 2022-02-24 2022-02-25 2022-02-26 2022-02-27 2022-02-28 
##         26         26         26         26         26         26         26 
## 2022-03-01 2022-03-02 2022-03-03 2022-03-04 2022-03-05 2022-03-06 2022-03-07 
##         26         26         26         26         26         26         26 
## 2022-03-08 2022-03-09 2022-03-10 2022-03-11 2022-03-12 2022-03-13 2022-03-14 
##         26         26         26         26         26         26         26 
## 2022-03-15 2022-03-16 2022-03-17 2022-03-18 2022-03-19 2022-03-20 2022-03-21 
##         26         26         26         26         26         26         26 
## 2022-03-22 2022-03-23 2022-03-24 2022-03-25 2022-03-26 2022-03-27 2022-03-28 
##         26         26         26         26         26         26         26 
## 2022-03-29 2022-03-30 2022-03-31       전체 
##         26         26         26          1
table(airseoul1$region)
## 
##   강남구   강동구   강북구   강서구   관악구   광진구   구로구   금천구 
##       59       59       59       59       59       59       59       59 
##   노원구   도봉구 동대문구   동작구   마포구 서대문구   서초구   성동구 
##       59       59       59       59       59       59       59       59 
##   성북구   송파구   양천구 영등포구   용산구   은평구   종로구     중구 
##       59       59       59       59       59       59       59       59 
##   중랑구     평균 
##       59       60
airseoul1<-airseoul1 %>% filter(date!="전체"&region!="평균")
table(airseoul1$date)
## 
## 2022-02-01 2022-02-02 2022-02-03 2022-02-04 2022-02-05 2022-02-06 2022-02-07 
##         25         25         25         25         25         25         25 
## 2022-02-08 2022-02-09 2022-02-10 2022-02-11 2022-02-12 2022-02-13 2022-02-14 
##         25         25         25         25         25         25         25 
## 2022-02-15 2022-02-16 2022-02-17 2022-02-18 2022-02-19 2022-02-20 2022-02-21 
##         25         25         25         25         25         25         25 
## 2022-02-22 2022-02-23 2022-02-24 2022-02-25 2022-02-26 2022-02-27 2022-02-28 
##         25         25         25         25         25         25         25 
## 2022-03-01 2022-03-02 2022-03-03 2022-03-04 2022-03-05 2022-03-06 2022-03-07 
##         25         25         25         25         25         25         25 
## 2022-03-08 2022-03-09 2022-03-10 2022-03-11 2022-03-12 2022-03-13 2022-03-14 
##         25         25         25         25         25         25         25 
## 2022-03-15 2022-03-16 2022-03-17 2022-03-18 2022-03-19 2022-03-20 2022-03-21 
##         25         25         25         25         25         25         25 
## 2022-03-22 2022-03-23 2022-03-24 2022-03-25 2022-03-26 2022-03-27 2022-03-28 
##         25         25         25         25         25         25         25 
## 2022-03-29 2022-03-30 2022-03-31 
##         25         25         25
table(airseoul1$region)
## 
##   강남구   강동구   강북구   강서구   관악구   광진구   구로구   금천구 
##       59       59       59       59       59       59       59       59 
##   노원구   도봉구 동대문구   동작구   마포구 서대문구   서초구   성동구 
##       59       59       59       59       59       59       59       59 
##   성북구   송파구   양천구 영등포구   용산구   은평구   종로구     중구 
##       59       59       59       59       59       59       59       59 
##   중랑구 
##       59
summary(airseoul1$pm10)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max.    NA's 
##    3.00   27.00   36.00   40.54   50.00  112.00       7
summary(airseoul1$pm2.5)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max.    NA's 
##    1.00   13.00   19.00   23.28   32.00   92.00       3
airseoul1<-airseoul1%>%filter(!is.na(pm10)&!is.na(pm2.5))

airseoul1 %>% filter(pm10==max(pm10)) %>% select(date,region,pm10)
## # A tibble: 1 × 3
##   date       region  pm10
##   <chr>      <chr>  <dbl>
## 1 2022-03-05 구로구   112
airseoul1 %>% filter(pm10==min(pm10)) %>% select(date,region,pm10)
## # A tibble: 3 × 3
##   date       region  pm10
##   <chr>      <chr>  <dbl>
## 1 2022-03-19 은평구     3
## 2 2022-03-18 도봉구     3
## 3 2022-03-18 은평구     3
airseoul1 %>% group_by(region) %>% summarise(m=mean(pm10)) %>%
  arrange(desc(m)) %>% head(5)
## # A tibble: 5 × 2
##   region     m
##   <chr>  <dbl>
## 1 양천구  44.4
## 2 강북구  44.2
## 3 강서구  43.8
## 4 노원구  43.7
## 5 강동구  43.6
airseoul1 %>% mutate(pm_grade=ifelse(pm10<=30,"good",
                                     ifelse(pm10<=81,"nomal",
                                     ifelse(pm10<150,"bad","worse")))) %>%
  group_by(pm_grade) %>% summarize(n=n()) %>% 
  mutate(total=sum(n),pct=n/total*100)
## # A tibble: 3 × 4
##   pm_grade     n total   pct
##   <chr>    <int> <int> <dbl>
## 1 bad         71  1467  4.84
## 2 good       538  1467 36.7 
## 3 nomal      858  1467 58.5
airseoul1 %>% filter(pm2.5==min(pm2.5)) %>% arrange(desc(pm10))
## # A tibble: 6 × 4
##   date       region    pm10 pm2.5
##   <chr>      <chr>    <dbl> <dbl>
## 1 2022-03-18 성동구       7     1
## 2 2022-03-18 구로구       6     1
## 3 2022-03-18 서초구       6     1
## 4 2022-03-19 구로구       5     1
## 5 2022-03-18 서대문구     5     1
## 6 2022-03-19 종로구       4     1