Thao tác thực hành dataset
data(trees)
d <- trees
str(d)
## 'data.frame': 31 obs. of 3 variables:
## $ Girth : num 8.3 8.6 8.8 10.5 10.7 10.8 11 11 11.1 11.2 ...
## $ Height: num 70 65 63 72 81 83 66 75 80 75 ...
## $ Volume: num 10.3 10.3 10.2 16.4 18.8 19.7 15.6 18.2 22.6 19.9 ...
names(d) <- c('G','H','V')
head(d)
## G H V
## 1 8.3 70 10.3
## 2 8.6 65 10.3
## 3 8.8 63 10.2
## 4 10.5 72 16.4
## 5 10.7 81 18.8
## 6 10.8 83 19.7
vol <- d$V
vol
## [1] 10.3 10.3 10.2 16.4 18.8 19.7 15.6 18.2 22.6 19.9 24.2 21.0 21.4 21.3 19.1
## [16] 22.2 33.8 27.4 25.7 24.9 34.5 31.7 36.3 38.3 42.6 55.4 55.7 58.3 51.5 51.0
## [31] 77.0
v15 <- vol[vol>15 & vol < 50]
v15
## [1] 16.4 18.8 19.7 15.6 18.2 22.6 19.9 24.2 21.0 21.4 21.3 19.1 22.2 33.8 27.4
## [16] 25.7 24.9 34.5 31.7 36.3 38.3 42.6
voll <- d[d$V >15 | d$H <60,]
voll
## G H V
## 4 10.5 72 16.4
## 5 10.7 81 18.8
## 6 10.8 83 19.7
## 7 11.0 66 15.6
## 8 11.0 75 18.2
## 9 11.1 80 22.6
## 10 11.2 75 19.9
## 11 11.3 79 24.2
## 12 11.4 76 21.0
## 13 11.4 76 21.4
## 14 11.7 69 21.3
## 15 12.0 75 19.1
## 16 12.9 74 22.2
## 17 12.9 85 33.8
## 18 13.3 86 27.4
## 19 13.7 71 25.7
## 20 13.8 64 24.9
## 21 14.0 78 34.5
## 22 14.2 80 31.7
## 23 14.5 74 36.3
## 24 16.0 72 38.3
## 25 16.3 77 42.6
## 26 17.3 81 55.4
## 27 17.5 82 55.7
## 28 17.9 80 58.3
## 29 18.0 80 51.5
## 30 18.0 80 51.0
## 31 20.6 87 77.0
d$logv <- log(d$V)
d$logh <- log(d$H)
d$tong <- d$G+d$H+d$V
cut(vol,4)
## [1] (10.1,26.9] (10.1,26.9] (10.1,26.9] (10.1,26.9] (10.1,26.9] (10.1,26.9]
## [7] (10.1,26.9] (10.1,26.9] (10.1,26.9] (10.1,26.9] (10.1,26.9] (10.1,26.9]
## [13] (10.1,26.9] (10.1,26.9] (10.1,26.9] (10.1,26.9] (26.9,43.6] (26.9,43.6]
## [19] (10.1,26.9] (10.1,26.9] (26.9,43.6] (26.9,43.6] (26.9,43.6] (26.9,43.6]
## [25] (26.9,43.6] (43.6,60.3] (43.6,60.3] (43.6,60.3] (43.6,60.3] (43.6,60.3]
## [31] (60.3,77.1]
## Levels: (10.1,26.9] (26.9,43.6] (43.6,60.3] (60.3,77.1]
table(cut(vol,4))
##
## (10.1,26.9] (26.9,43.6] (43.6,60.3] (60.3,77.1]
## 18 7 5 1
bo du lieu iris
data("iris")
cut(iris$Sepal.Length,4)
## [1] (4.3,5.2] (4.3,5.2] (4.3,5.2] (4.3,5.2] (4.3,5.2] (5.2,6.1] (4.3,5.2]
## [8] (4.3,5.2] (4.3,5.2] (4.3,5.2] (5.2,6.1] (4.3,5.2] (4.3,5.2] (4.3,5.2]
## [15] (5.2,6.1] (5.2,6.1] (5.2,6.1] (4.3,5.2] (5.2,6.1] (4.3,5.2] (5.2,6.1]
## [22] (4.3,5.2] (4.3,5.2] (4.3,5.2] (4.3,5.2] (4.3,5.2] (4.3,5.2] (4.3,5.2]
## [29] (4.3,5.2] (4.3,5.2] (4.3,5.2] (5.2,6.1] (4.3,5.2] (5.2,6.1] (4.3,5.2]
## [36] (4.3,5.2] (5.2,6.1] (4.3,5.2] (4.3,5.2] (4.3,5.2] (4.3,5.2] (4.3,5.2]
## [43] (4.3,5.2] (4.3,5.2] (4.3,5.2] (4.3,5.2] (4.3,5.2] (4.3,5.2] (5.2,6.1]
## [50] (4.3,5.2] (6.1,7] (6.1,7] (6.1,7] (5.2,6.1] (6.1,7] (5.2,6.1]
## [57] (6.1,7] (4.3,5.2] (6.1,7] (4.3,5.2] (4.3,5.2] (5.2,6.1] (5.2,6.1]
## [64] (5.2,6.1] (5.2,6.1] (6.1,7] (5.2,6.1] (5.2,6.1] (6.1,7] (5.2,6.1]
## [71] (5.2,6.1] (5.2,6.1] (6.1,7] (5.2,6.1] (6.1,7] (6.1,7] (6.1,7]
## [78] (6.1,7] (5.2,6.1] (5.2,6.1] (5.2,6.1] (5.2,6.1] (5.2,6.1] (5.2,6.1]
## [85] (5.2,6.1] (5.2,6.1] (6.1,7] (6.1,7] (5.2,6.1] (5.2,6.1] (5.2,6.1]
## [92] (5.2,6.1] (5.2,6.1] (4.3,5.2] (5.2,6.1] (5.2,6.1] (5.2,6.1] (6.1,7]
## [99] (4.3,5.2] (5.2,6.1] (6.1,7] (5.2,6.1] (7,7.9] (6.1,7] (6.1,7]
## [106] (7,7.9] (4.3,5.2] (7,7.9] (6.1,7] (7,7.9] (6.1,7] (6.1,7]
## [113] (6.1,7] (5.2,6.1] (5.2,6.1] (6.1,7] (6.1,7] (7,7.9] (7,7.9]
## [120] (5.2,6.1] (6.1,7] (5.2,6.1] (7,7.9] (6.1,7] (6.1,7] (7,7.9]
## [127] (6.1,7] (5.2,6.1] (6.1,7] (7,7.9] (7,7.9] (7,7.9] (6.1,7]
## [134] (6.1,7] (5.2,6.1] (7,7.9] (6.1,7] (6.1,7] (5.2,6.1] (6.1,7]
## [141] (6.1,7] (6.1,7] (5.2,6.1] (6.1,7] (6.1,7] (6.1,7] (6.1,7]
## [148] (6.1,7] (6.1,7] (5.2,6.1]
## Levels: (4.3,5.2] (5.2,6.1] (6.1,7] (7,7.9]
table(cut(iris$Sepal.Length,4),iris$Species)
##
## setosa versicolor virginica
## (4.3,5.2] 39 5 1
## (5.2,6.1] 11 29 10
## (6.1,7] 0 16 27
## (7,7.9] 0 0 12