Dear all,
I have a matrix X with 47 lines and say 500 columns - values are in {0,1}.
I'd like to compare lines.
For that, I first did:
for (i in 1:(dim(X)[1]-1))
for (j in (i+1):dim(X)[1]) {
Y <- X[i,]+Y[j,]
etc.
but, since it takes a long time, I would prefer avoding loops;
for that, my first idea was to add this matrix:
X1=X[,rep(1:46,46:1)]
to this one:
res=NULL
for (i in (2:47)) res=c(res,i:47)
X2=X[,res]
(Is it a nice alternative way ?)
Is there a way to create the second matrix X2 without a loop, such as for X1
?
Thanks in advance,
Jacques VESLOT
______________________________________________
[email protected] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
