> x=array(runif(24),c(4,3,2))
> x
, , 1
[,1] [,2] [,3]
[1,] 0.6953832 0.8209977 0.38583214
[2,] 0.4993301 0.5251950 0.04634707
[3,] 0.8219069 0.1761397 0.66012447
[4,] 0.1118249 0.7220923 0.46044622
, , 2
[,1] [,2] [,3]
[1,] 0.8021535 0.6029162 0.6863334
[2,] 0.5999509 0.4068553 0.8726527
[3,] 0.9140723 0.4912114 0.6791098
[4,] 0.5755712 0.1285849 0.4201371
> is.matrix(x)
[1] FALSE
> dim(x)
[1] 4 3 2
> is.matrix(x[1,,])
[1] TRUE
> x=array(1:24,c(4,3,2))
> x
, , 1
[,1] [,2] [,3]
[1,] 1 5 9
[2,] 2 6 10
[3,] 3 7 11
[4,] 4 8 12
, , 2
[,1] [,2] [,3]
[1,] 13 17 21
[2,] 14 18 22
[3,] 15 19 23
[4,] 16 20 24
> apply(x,1,mean)
[1] 11 12 13 14
> apply(x,1,sum)
[1] 66 72 78 84
> apply(x,1:2,sum)
[,1] [,2] [,3]
[1,] 14 22 30
[2,] 16 24 32
[3,] 18 26 34
[4,] 20 28 36
> apply(x,c(1,3),sum)
[,1] [,2]
[1,] 15 51
[2,] 18 54
[3,] 21 57
[4,] 24 60
> x=matrix(1:20,5,4)
> x
[,1] [,2] [,3] [,4]
[1,] 1 6 11 16
[2,] 2 7 12 17
[3,] 3 8 13 18
[4,] 4 9 14 19
[5,] 5 10 15 20
> sweep(x,1,1:5,"*")
[,1] [,2] [,3] [,4]
[1,] 1 6 11 16
[2,] 4 14 24 34
[3,] 9 24 39 54
[4,] 16 36 56 76
[5,] 25 50 75 100
> sweep(x,x,1:4,"+")
Error in if (lstats > prod(dimmargin)) { :
missing value where TRUE/FALSE needed
> sweep(x,2,1:4,"+")
[,1] [,2] [,3] [,4]
[1,] 2 8 14 20
[2,] 3 9 15 21
[3,] 4 10 16 22
[4,] 5 11 17 23
[5,] 6 12 18 24
> x*1:5
[,1] [,2] [,3] [,4]
[1,] 1 6 11 16
[2,] 4 14 24 34
[3,] 9 24 39 54
[4,] 16 36 56 76
[5,] 25 50 75 100
> x
[,1] [,2] [,3] [,4]
[1,] 1 6 11 16
[2,] 2 7 12 17
[3,] 3 8 13 18
[4,] 4 9 14 19
[5,] 5 10 15 20
> #下面把x标准化，即每一元素减去该列均值，除以该列标准差
> (x=matrix(sample(1:100,24),6,4))
[,1] [,2] [,3] [,4]
[1,] 15 95 13 83
[2,] 86 50 32 75
[3,] 7 25 4 92
[4,] 71 26 93 1
[5,] 18 34 20 35
[6,] 61 47 87 73
> x1=scale(x)
> x1
[,1] [,2] [,3] [,4]
[1,] -0.8320666 1.87189305 -0.7361859 0.6658389
[2,] 1.2778166 0.14694041 -0.2453953 0.4359090
[3,] -1.0697999 -0.81136661 -0.9686657 0.9245102
[4,] 0.8320666 -0.77303433 1.3303009 -1.6909435
[5,] -0.7429166 -0.46637609 -0.5553683 -0.7137410
[6,] 0.5349000 0.03194357 1.1753144 0.3784265
attr(,"scaled:center")
[1] 43.00000 46.16667 41.50000 59.83333
attr(,"scaled:scale")
[1] 33.65115 26.08767 38.71305 34.79320
> x2=scale(x,scale=F)
> x2
[,1] [,2] [,3] [,4]
[1,] -28 48.8333333 -28.5 23.16667
[2,] 43 3.8333333 -9.5 15.16667
[3,] -36 -21.1666667 -37.5 32.16667
[4,] 28 -20.1666667 51.5 -58.83333
[5,] -25 -12.1666667 -21.5 -24.83333
[6,] 18 0.8333333 45.5 13.16667
attr(,"scaled:center")
[1] 43.00000 46.16667 41.50000 59.83333
> apply(x,1,mean)
[1] 51.50 60.75 32.00 47.75 26.75 67.00
> apply(x,3,mean)
Error in if (d2 == 0L) { : missing value where TRUE/FALSE needed
> apply(x,2,mean)
[1] 43.00000 46.16667 41.50000 59.83333
> x3=scale(x,center=F)
> x3
[,1] [,2] [,3] [,4]
[1,] 0.2591141 1.6694437 0.21771544 1.11850087
[2,] 1.4855876 0.8786546 0.53591492 1.01069356
[3,] 0.1209199 0.4393273 0.06698937 1.23978410
[4,] 1.2264735 0.4569004 1.55750274 0.01347591
[5,] 0.3109369 0.5974851 0.33494683 0.47165699
[6,] 1.0537308 0.8259353 1.45701869 0.98374173
attr(,"scaled:scale")
[1] 57.88955 56.90518 59.71097 74.20647
> round(apply(x1,2,mean),14)
[1] 0 0 0 0
> apply(x1,2,sd)
[1] 1 1 1 1
> apply(x,2,sd)
[1] 33.65115 26.08767 38.71305 34.79320
> 28/33
[1] 0.8484848
> 28/33.65115
[1] 0.8320667
> x2
[,1] [,2] [,3] [,4]
[1,] -28 48.8333333 -28.5 23.16667
[2,] 43 3.8333333 -9.5 15.16667
[3,] -36 -21.1666667 -37.5 32.16667
[4,] 28 -20.1666667 51.5 -58.83333
[5,] -25 -12.1666667 -21.5 -24.83333
[6,] 18 0.8333333 45.5 13.16667
attr(,"scaled:center")
[1] 43.00000 46.16667 41.50000 59.83333
> x3
[,1] [,2] [,3] [,4]
[1,] 0.2591141 1.6694437 0.21771544 1.11850087
[2,] 1.4855876 0.8786546 0.53591492 1.01069356
[3,] 0.1209199 0.4393273 0.06698937 1.23978410
[4,] 1.2264735 0.4569004 1.55750274 0.01347591
[5,] 0.3109369 0.5974851 0.33494683 0.47165699
[6,] 1.0537308 0.8259353 1.45701869 0.98374173
attr(,"scaled:scale")
[1] 57.88955 56.90518 59.71097 74.20647
> round(apply(x2,2,mean),14)
[1] 0 0 0 0
> round(apply(x2,2,sd),14)
[1] 33.65115 26.08767 38.71305 34.79320
> round(apply(x3,2,sd),14)
[1] 0.5812992 0.4584411 0.6483406 0.4688702
> 33.65115*0.2591141
[1] 8.719487
> round(apply(x3,2,mean),14)
[1] 0.7427938 0.8112910 0.6950147 0.8063089
> 43+28
[1] 71
> -x
[,1] [,2] [,3] [,4]
[1,] -15 -95 -13 -83
[2,] -86 -50 -32 -75
[3,] -7 -25 -4 -92
[4,] -71 -26 -93 -1
[5,] -18 -34 -20 -35
[6,] -61 -47 -87 -73
> x
[,1] [,2] [,3] [,4]
[1,] 15 95 13 83
[2,] 86 50 32 75
[3,] 7 25 4 92
[4,] 71 26 93 1
[5,] 18 34 20 35
[6,] 61 47 87 73
> 86-7
[1] 79
> 15/79
[1] 0.1898734
> x3
[,1] [,2] [,3] [,4]
[1,] 0.2591141 1.6694437 0.21771544 1.11850087
[2,] 1.4855876 0.8786546 0.53591492 1.01069356
[3,] 0.1209199 0.4393273 0.06698937 1.23978410
[4,] 1.2264735 0.4569004 1.55750274 0.01347591
[5,] 0.3109369 0.5974851 0.33494683 0.47165699
[6,] 1.0537308 0.8259353 1.45701869 0.98374173
attr(,"scaled:scale")
[1] 57.88955 56.90518 59.71097 74.20647
> x
[,1] [,2] [,3] [,4]
[1,] 15 95 13 83
[2,] 86 50 32 75
[3,] 7 25 4 92
[4,] 71 26 93 1
[5,] 18 34 20 35
[6,] 61 47 87 73
> 15/33.65115
[1] 0.44575
> round(apply(x,2,sd),14)
[1] 33.65115 26.08767 38.71305 34.79320
> x
[,1] [,2] [,3] [,4]
[1,] 15 95 13 83
[2,] 86 50 32 75
[3,] 7 25 4 92
[4,] 71 26 93 1
[5,] 18 34 20 35
[6,] 61 47 87 73
> 15/33.65115
[1] 0.44575
> x3=scale(x,center=F)
> x3
[,1] [,2] [,3] [,4]
[1,] 0.2591141 1.6694437 0.21771544 1.11850087
[2,] 1.4855876 0.8786546 0.53591492 1.01069356
[3,] 0.1209199 0.4393273 0.06698937 1.23978410
[4,] 1.2264735 0.4569004 1.55750274 0.01347591
[5,] 0.3109369 0.5974851 0.33494683 0.47165699
[6,] 1.0537308 0.8259353 1.45701869 0.98374173
attr(,"scaled:scale")
[1] 57.88955 56.90518 59.71097 74.20647
> 0.2591141*57.88955
[1] 15
> 1.4855876*57.88955
[1] 86
一些R命令（5）
猜你喜欢
转载自blog.csdn.net/feynman1999/article/details/81137670
今日推荐
周排行