R help - Aug 2000 - How to?

Hi,

Is there a way to apply a function to rows or columns of a matrix?

Now I use apply(as.matrix(1:nrow(m), 1, function(x) mean(m[x,])) which works
fine but kind of slow on large matrix. I'm sure there is something on this
somewhere but I can't find it.

Thanks

Yves Gauvreau

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"Yves Gauvreau" <cyg at sympatico.ca> writes:
> Is there a way to apply a function to rows or columns of a matrix?
> 
> Now I use apply(as.matrix(1:nrow(m), 1, function(x) mean(m[x,])) which
works
> fine but kind of slow on large matrix. I'm sure there is something on
this
> somewhere but I can't find it.
Er, how about

apply(m,1,mean)

??

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