R语言实战-数据类型-1(标量、向量、矩阵、数组）

1 a<-c(1,2,3,4)
2 b<-c('aa','bb','cc')
3 c<-c(TRUE,FALSE,TRUE)

1 > d<-a[c(1,3)]
2 > d
3 [1] 1 3
4 > e<-a[2:4]
5 > e
6 [1] 2 3 4
7 > f<-a[3]
8 > f
9 [1] 3

 1 matrix(1:21,nrow = 5)
 2      [,1] [,2] [,3] [,4] [,5]
 3 [1,]    1    6   11   16   21
 4 [2,]    2    7   12   17    1
 5 [3,]    3    8   13   18    2
 6 [4,]    4    9   14   19    3
 7 [5,]    5   10   15   20    4
 8 Warning message:
 9 In matrix(1:21, nrow = 5) :
10   data length [21] is not a sub-multiple or multiple of the number of rows [5]
11 > 

 1  matrix(1:21,nrow = 5,byrow = TRUE)
 2      [,1] [,2] [,3] [,4] [,5]
 3 [1,]    1    2    3    4    5
 4 [2,]    6    7    8    9   10
 5 [3,]   11   12   13   14   15
 6 [4,]   16   17   18   19   20
 7 [5,]   21    1    2    3    4
 8 Warning message:
 9 In matrix(1:21, nrow = 5, byrow = TRUE) :
10   data length [21] is not a sub-multiple or multiple of the number of rows [5]

 1 > x[2,]
 2 [1]  6  7  8  9 10
 3 > x[,2]
 4 [1]  2  7 12 17 22
 5 > x[2,2]
 6 [1] 7
 7 > x[3,3]
 8 [1] 13
 9 > x[c(1,3),]
10      [,1] [,2] [,3] [,4] [,5]
11 [1,]    1    2    3    4    5
12 [2,]   11   12   13   14   15
13 > x[c(1,3),c(2,4)]
14      [,1] [,2]
15 [1,]    2    4
16 [2,]   12   14
17 > x[1:3,]
18      [,1] [,2] [,3] [,4] [,5]
19 [1,]    1    2    3    4    5
20 [2,]    6    7    8    9   10
21 [3,]   11   12   13   14   15

  1 > y<-array(1:100,dim = c(2,2,5,5),
  2 +          dimnames = list(
  3 +            c('a1','a2'),
  4 +            c('b1','b2'),
  5 +            c('c1','c2','c3','c4','c5'),
  6 +            c('d1','d2','d3','d4','d5')))
  7 > y
  8 , , c1, d1
  9 
 10    b1 b2
 11 a1  1  3
 12 a2  2  4
 13 
 14 , , c2, d1
 15 
 16    b1 b2
 17 a1  5  7
 18 a2  6  8
 19 
 20 , , c3, d1
 21 
 22    b1 b2
 23 a1  9 11
 24 a2 10 12
 25 
 26 , , c4, d1
 27 
 28    b1 b2
 29 a1 13 15
 30 a2 14 16
 31 
 32 , , c5, d1
 33 
 34    b1 b2
 35 a1 17 19
 36 a2 18 20
 37 
 38 , , c1, d2
 39 
 40    b1 b2
 41 a1 21 23
 42 a2 22 24
 43 
 44 , , c2, d2
 45 
 46    b1 b2
 47 a1 25 27
 48 a2 26 28
 49 
 50 , , c3, d2
 51 
 52    b1 b2
 53 a1 29 31
 54 a2 30 32
 55 
 56 , , c4, d2
 57 
 58    b1 b2
 59 a1 33 35
 60 a2 34 36
 61 
 62 , , c5, d2
 63 
 64    b1 b2
 65 a1 37 39
 66 a2 38 40
 67 
 68 , , c1, d3
 69 
 70    b1 b2
 71 a1 41 43
 72 a2 42 44
 73 
 74 , , c2, d3
 75 
 76    b1 b2
 77 a1 45 47
 78 a2 46 48
 79 
 80 , , c3, d3
 81 
 82    b1 b2
 83 a1 49 51
 84 a2 50 52
 85 
 86 , , c4, d3
 87 
 88    b1 b2
 89 a1 53 55
 90 a2 54 56
 91 
 92 , , c5, d3
 93 
 94    b1 b2
 95 a1 57 59
 96 a2 58 60
 97 
 98 , , c1, d4
 99 
100    b1 b2
101 a1 61 63
102 a2 62 64
103 
104 , , c2, d4
105 
106    b1 b2
107 a1 65 67
108 a2 66 68
109 
110 , , c3, d4
111 
112    b1 b2
113 a1 69 71
114 a2 70 72
115 
116 , , c4, d4
117 
118    b1 b2
119 a1 73 75
120 a2 74 76
121 
122 , , c5, d4
123 
124    b1 b2
125 a1 77 79
126 a2 78 80
127 
128 , , c1, d5
129 
130    b1 b2
131 a1 81 83
132 a2 82 84
133 
134 , , c2, d5
135 
136    b1 b2
137 a1 85 87
138 a2 86 88
139 
140 , , c3, d5
141 
142    b1 b2
143 a1 89 91
144 a2 90 92
145 
146 , , c4, d5
147 
148    b1 b2
149 a1 93 95
150 a2 94 96
151 
152 , , c5, d5
153 
154    b1  b2
155 a1 97  99
156 a2 98 100

 1 > y[1,2,3,4]
 2 [1] 71
 3 > y[1,2,1:2,2:3]
 4    d2 d3
 5 c1 23 43
 6 c2 27 47
 7 > y[1,c(1,2),2:4,c(1,3,5)]
 8 , , d1
 9 
10    c2 c3 c4
11 b1  5  9 13
12 b2  7 11 15
13 
14 , , d3
15 
16    c2 c3 c4
17 b1 45 49 53
18 b2 47 51 55
19 
20 , , d5
21 
22    c2 c3 c4
23 b1 85 89 93
24 b2 87 91 95

1 > y[c('a2'),'b2','c2','d2']
2 [1] 28
3 > y[c('a2'),'b2','c2',c('d2','d3')]
4 d2 d3 
5 28 48