[R] Question about NA's

[Matthias Tips]

Hi,

i got a little question about the NA's in vectors and matrices. When I 
want to do some operations on a matrix with some NA's it is possible 
to stripp them before the computation proceed (by na.rm=TRUE).

But how can I stripp NA's when I want to proceed a 'if', 'for' 
or 'while' string? Because when I don't stripp them I always reveive 
the message :"missing value where TRUE/FALSE needed". I don't know if 
I can use the method with na.rm=TRUE and if so, how I can do it.

Thanks a lot in advance!

Matthias Tips