Creating vectors

 x=c(1, 2, 3)
 > x

Functions to generate vectors

 > x=1:10
 > x
  [1]  1  2  3  4  5  6  7  8  9 10

 > x=seq(10)
 > x
  [1]  1  2  3  4  5  6  7  8  9 10


> x=seq(1,20,2)
> x
 [1]  1  3  5  7  9 11 13 15 17 19


> x=rep(10,5)
> x
 [1] 10 10 10 10 10

Summary Statistics

 > x <-c(1,3,5,7,9,2,4,6,8,-1)
 > summary(x)
    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
   -1.00    2.25    4.50    4.40    6.75    9.00 

Statistical functions

 > x <-c(1,3,5,7,9,2,4,6,8,-1)

 > length(x)
 [1] 10

 > min(x)
 [1] -1

 > max(x)
 [1] 9

 > sort(x)
  [1] -1  1  2  3  4  5  6  7  8  9



 > median(x)
 [1] 4.5

 > mean(x)
 [1] 4.4

 > sd(x)
 [1] 3.204164

 > var(x)
 [1] 10.26667

 > quantile(x,0.25)
  25% 
 2.25 

 > quantile(x,0.75)
  75% 
 6.75