hk0316 Exercise-2
Tung-Han Wu
2020/3/16
all possible sums from rolling three dice using R
set.seed(123)
sort(sample(3:18, size=16, replace=F, prob=c(1/216, 3/216, 6/216, 10/216, 15/216, 21/216, 25/216, 27/216, 27/216, 25/216, 21/216, 15/216, 10/216, 6/216, 3/216, 1/216)))## [1] 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18dice1 <- sample(1:6, 1000, rep=T) # rep=T 重複抽嗎
dice2 <- sample(1:6, 1000, rep=T)
dice3 <- sample(1:6, 1000, rep=T)
hist(dice1+dice2+dice3)
#the polt is empirical histogram
outer function
PPT page 30
dice <- outer(1:6, 1:6, '+')
list(dice)## [[1]]
## [,1] [,2] [,3] [,4] [,5] [,6]
## [1,] 2 3 4 5 6 7
## [2,] 3 4 5 6 7 8
## [3,] 4 5 6 7 8 9
## [4,] 5 6 7 8 9 10
## [5,] 6 7 8 9 10 11
## [6,] 7 8 9 10 11 12dice_3 <- outer(dice, 1:6, "+")
list(dice_3)## [[1]]
## , , 1
##
## [,1] [,2] [,3] [,4] [,5] [,6]
## [1,] 3 4 5 6 7 8
## [2,] 4 5 6 7 8 9
## [3,] 5 6 7 8 9 10
## [4,] 6 7 8 9 10 11
## [5,] 7 8 9 10 11 12
## [6,] 8 9 10 11 12 13
##
## , , 2
##
## [,1] [,2] [,3] [,4] [,5] [,6]
## [1,] 4 5 6 7 8 9
## [2,] 5 6 7 8 9 10
## [3,] 6 7 8 9 10 11
## [4,] 7 8 9 10 11 12
## [5,] 8 9 10 11 12 13
## [6,] 9 10 11 12 13 14
##
## , , 3
##
## [,1] [,2] [,3] [,4] [,5] [,6]
## [1,] 5 6 7 8 9 10
## [2,] 6 7 8 9 10 11
## [3,] 7 8 9 10 11 12
## [4,] 8 9 10 11 12 13
## [5,] 9 10 11 12 13 14
## [6,] 10 11 12 13 14 15
##
## , , 4
##
## [,1] [,2] [,3] [,4] [,5] [,6]
## [1,] 6 7 8 9 10 11
## [2,] 7 8 9 10 11 12
## [3,] 8 9 10 11 12 13
## [4,] 9 10 11 12 13 14
## [5,] 10 11 12 13 14 15
## [6,] 11 12 13 14 15 16
##
## , , 5
##
## [,1] [,2] [,3] [,4] [,5] [,6]
## [1,] 7 8 9 10 11 12
## [2,] 8 9 10 11 12 13
## [3,] 9 10 11 12 13 14
## [4,] 10 11 12 13 14 15
## [5,] 11 12 13 14 15 16
## [6,] 12 13 14 15 16 17
##
## , , 6
##
## [,1] [,2] [,3] [,4] [,5] [,6]
## [1,] 8 9 10 11 12 13
## [2,] 9 10 11 12 13 14
## [3,] 10 11 12 13 14 15
## [4,] 11 12 13 14 15 16
## [5,] 12 13 14 15 16 17
## [6,] 13 14 15 16 17 18the histogram plot and it’s just a probability histogram, not an empirical histogram.
hist(dice_3)