Hello
Please see the example below > class(testX) [1] "matrix" > class(testX[1,]) [1] "numeric" Why not matrix? What am I missing here? Is there a way to keep the same class? The reason for the question is that I want to implement a k-step ahead prediction for my own routines and R wrecks does not seem to like [1,] as shown below. > predict(fit10,testX[1,]) Error in knnregTrain(train = c(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, : dims of 'test' and 'train differ > predict(fit10,testX[1:2,]) [1] 81.00 76.36 Many thanks Ed [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.