Data Steps / Creating Data

Crating data

using c(...)

> y=c(1,2,3,4,5)

> y

[1] 1 2 3 4 5

use of : for from:to

> x<-1:10

> x

 [1]  1  2  3  4  5  6  7  8  9 10

using seq()

> a<-seq(1,10, 0.5); b<-seq(1,10, by =0.5)

> a

 [1]  1.0  1.5  2.0  2.5  3.0  3.5  4.0  4.5  5.0  5.5  6.0  6.5  7.0  7.5  8.0

[16]  8.5  9.0  9.5 10.0

> b

 [1]  1.0  1.5  2.0  2.5  3.0  3.5  4.0  4.5  5.0  5.5  6.0  6.5  7.0  7.5  8.0

[16]  8.5  9.0  9.5 10.0

> c<-seq(1,10, length=10); d=seq(1,10, length=15) # did I say that "<-" and "=" both assigns value

> c

 [1]  1  2  3  4  5  6  7  8  9 10

> d

 [1]  1.000000  1.642857  2.285714  2.928571  3.571429  4.214286  4.857143

 [8]  5.500000  6.142857  6.785714  7.428571  8.071429  8.714286  9.357143

[15] 10.000000

> f=seq(1,10, by=2); g=seq(1,10, by=3)

> f

[1] 1 3 5 7 9

> g

[1]  1  4  7 10

using rep()

> h=rep(1:5,2); i=rep(1:5, times=2)

> h

 [1] 1 2 3 4 5 1 2 3 4 5

> i

 [1] 1 2 3 4 5 1 2 3 4 5

> j=rep(1:5, each=2); k=rep(1:5, c(2,3,1,2,2))

> j

 [1] 1 1 2 2 3 3 4 4 5 5

> k

 [1] 1 1 2 2 2 3 4 4 5 5

> l=rep(1:5, each=3 , times=2)

> l

 [1] 1 1 1 2 2 2 3 3 3 4 4 4 5 5 5 1 1 1 2 2 2 3 3 3 4 4 4 5 5 5

> m=rep(1:5, each=2, len=8);n=rep(1:5, each=2, len=12)

> m

[1] 1 1 2 2 3 3 4 4

> n

 [1] 1 1 2 2 3 3 4 4 5 5 1 1

use of gl to make factors

> gl(4,5)

 [1] 1 1 1 1 1 2 2 2 2 2 3 3 3 3 3 4 4 4 4 4

Levels: 1 2 3 4

> gl(4,5, labels=c("A","B","C","D"))

 [1] A A A A A B B B B B C C C C C D D D D D

Levels: A B C D

> gl(4,1,20)

 [1] 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4

Levels: 1 2 3 4

use of sequence

> sequence(c(8:1))

 [1] 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 1 2 3 4 5 6 1 2 3 4 5 1 2 3 4 1 2 3 1 2 1