(no subject)

Please read the posting guide that tells you to a) use a meaningful
subject line b) give a reproducible example if you can c) read the
manuals and help files first

If you have a vector (not a list) of numbers, say x, and you want to
center it on the median you can do

x <- c(1,2,3,4,5)

Then x - median(x) will give you the deviation of x from its median.
Note that operations in R is vectorised, so you do not need to to do
something like "for(i in 1:5) y[i] <- x[i] - median(x)".

Next you want to square this deviation and sum over all elements.

d <- x - median(x)
sum( d^2 )

Or you can do it in one line as  "sum( (x - median(x))^2 )"

Hi, 

 

I have a list of numbers. For each of the numbers, I take sum of squares of
the numbers centered on the number chosen. If it is less than a certain
constant, I will take the average of the numbers chosen.  

 

Anyone can give me a sample code. You help will be greatly appreciated. 

 

Peter


	[[alternative HTML version deleted]]

______________________________________________
R-help at stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html

Adaikalavan Ramasamy                    ramasamy at cancer.org.uk
Centre for Statistics in Medicine       http://www.ihs.ox.ac.uk/csm/
Cancer Research UK                      Tel : 01865 226 677
Old Road Campus, Headington, Oxford     Fax : 01865 226 962