[R] ifelse, evaluating to given number

[Peter Wilkinson]

I would like to take advantage of the  vectorized 'ifelse' command. Given a 
filter number of 'filter', if the nm'th value in a n x m matrix I would 
like to perform the following.

newMatrix <- ifelse(myMat <=filter, filter+1, "existing nm'th value").

What do I use to express the "existing nm'th value" in this expression if I 
want to test an nm th value is less than 'filter', if false use the 
existing nm'th value.

This does not seem to be documented in the help().

Peter W.