[R] newbie question: ROW average

[Peter Dalgaard]

A Ezhil <ezhil02 at yahoo.com> writes:

> Hi,
> 
> I am new to R programming. I have a 992 x 74 matrix. I
> would like to form a new matrix by averging each 4
> rows
> from the original one. How can I use 'apply' instead
> of usual mean inside the nested for loop?

How about 

dim(M) <- c(4,248,74)
mn <- apply(M, c(2,3), mean)
 
(Yes, this is a bit confusing and easy to get wrong...)

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   O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
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