Hi all,
Suppose I have a vector x with numerical values.
In y, I have a categorial variable : y-c(1,1,..2,2,...30,30,30)
x and y have the same length.
I would like to compute the mean for x for the modality 1 to 30 in y.
mean(x[y==1]),...,mean(x[y==30])
I do not want to use an iterative procedure
Hi,
On 2/2/07, Martin Olivier [EMAIL PROTECTED] wrote:
Hi all,
Suppose I have a vector x with numerical values.
In y, I have a categorial variable : y-c(1,1,..2,2,...30,30,30)
x and y have the same length.
I would like to compute the mean for x for the modality 1 to 30 in y.
