-roger
Moises Hassan wrote:
It works great, except that in the case where only one column is left, it returns a vector and the column name is lost. How can you avoid that behavior?
Thanks, - Moises
-----Original Message-----
From: Spencer Graves [mailto:[EMAIL PROTECTED] Sent: Saturday, August 28, 2004 8:26 PM
To: Peter Dalgaard
Cc: Moises Hassan; R Help
Subject: Re: [R] removing invariant columns from a matrix
Both the previous solutions seem to assume a numeric matrix. How about the following:
A <- array(letters[c(rep(1, 13), rep(2, 13), 1:26)], dim=c(13, 5)) A[, apply(A, 2, function(x)any(x[-1] != x[-length(x)]))] A[, apply(A, 2, function(x)any(x[-1] != x[-length(x)])]
enjoy. spencer graves
Peter Dalgaard wrote:
"Moises Hassan" <[EMAIL PROTECTED]> writes:
I'm looking for an efficient way of removing zero-variance columns
from
a large matrix.
Any suggestions?
A[,apply(A,2,var)>0]
______________________________________________ [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
______________________________________________ [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
