Creating a Matrix from a vector with some conditions

Hi

Suppose we have an object with strings:

A<-c("a","b","c","d")

Now I do:

B<-matrix(A,4,4, byrow=F)

and I get

a a a a
b b b b
c c c c
d d d d

But what I really want is:

a b c d
b c d a
c d a b
d a b c

How can I do this?

Try the following

  v <- rep(c("a", "b", "c", "d"), times=2)
  a <- matrix(nrow=4, ncol=4)
  a[, ] <- v[row(a) + col(a) - 1]
  a
       [,1] [,2] [,3] [,4]
  [1,] "a"  "b"  "c"  "d" 
  [2,] "b"  "c"  "d"  "a" 
  [3,] "c"  "d"  "a"  "b" 
  [4,] "d"  "a"  "b"  "c" 

Petr Savicky.