[R] Calculate Mean of Column Vectors?

[Christoph Scherber]

Dear Thomas,

My suggestion would be as follows:

y <- rnorm(3000)
dim(y) <- c(3, 1000).

#then create three column vectors out of y using cbind():

w<-cbind(y[1,],y[2,],y[3,])

# and calculate the row means

for (i in 1:1000) z[i]<-mean(w[i,1:3])

z

Hope I got it right!

Regards,
Christoph




Thomas Hopper wrote:

> Hello,
>
> I've got an array defined as y <- rnorm(3000), dim(y) <- c(3, 1000).
>
> I'd like to produce a 1000-element vector z that is the mean of the 
> corresponding elements of y (like z[1,1] <- mean(y[1,1], y[2,1], 
> y[3,1])), but being new to R, I'm not sure how to do this for all 
> elements at once (or, at least, simply). Any help is appreciated.
>
> Thanks,
>
> Tom
>
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