[R] Getting multiple matrix-values using a single command

[Nils Rüfenacht]

Dear all!

I'm trying to get multiple values from a matrix by using a single  
command.

Given a matrix A

A <- matrix(seq(1,9),nrow=3,ncol=3)

How can I get e.g. the values A[1,2] = 4 and A[3,3] = 9 with a single  
command and without using any loop? My first idea was to generate a  
row- and a column vector for the indices, i.e. c(1,3) indicating row  
number 1 (for A[1,2]) and row number 3 (for A[3,3]) and similar for  
column-indices. Then I've tried to call

A[c(1,3),c(2,3)]

but instead of 4 , 9 the result is

[,1] [,2]
[1,]    4    7
[2,]    6    9

Any suggestions?

Regards, Nils