Hi, On Thu, May 13, 2010 at 3:54 PM, jparga <argaj...@yahoo.com.ar> wrote: > > Hello, I hope you can help me! > I`m trying to tune svm parameters: cost and gamma for a landsat image > classification, but I get an error and I can't understand it. > I write this: >> tune(svm, Class~., data = mdt01bis, ranges = list(gamma = 2^(-15:3), cost >> = 2^(-5:15))) > and R gives: > Error en predict.svm(model, if (!is.null(validation.x)) validation.x else if > (useFormula) data[-train.ind[[sample]], : > test data does not match model ! > > The matrix is as follows, with 720 rows and 4 categories in column Class > B1 B2 B3 B4 B5 B6 Class > [1,] "0.0450" "0.0599" "0.1169" "0.1820" "0.3040" "0.2826" "CV" > [2,] "0.0481" "0.0630" "0.1222" "0.1854" "0.3040" "0.2891" "CV" > [3,] "0.0497" "0.0630" "0.1329" "0.1988" "0.2929" "0.2794" "CV" > [4,] "0.0450" "0.0567" "0.1196" "0.1854" "0.2973" "0.2859" "CV" > > and the svm: >> svm(Class~., data=mdt01bis, method="C-classification", kernel="radial", >> cost=10, gamma=0.1) > works ok. > Could you please tell me what is wrong?
I'm not really sure, but the first red flag is that your numbers are stored as characters (B1, B2, etc. are strings) Also the formula interface expects a data.frame (an object which can have mixed column types) and not a matrix (an object that can only contain one type). Since one of your columns contains "CV", and you're trying to horseshoe all of you data into a matrix, perhaps all your numerical values are being upcast to characters, which is subsequently messing something up. -- Steve Lianoglou Graduate Student: Computational Systems Biology | Memorial Sloan-Kettering Cancer Center | Weill Medical College of Cornell University Contact Info: http://cbio.mskcc.org/~lianos/contact ______________________________________________ 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.
