Hi Thomas, On Wed, Mar 14, 2012 at 11:00 AM, Thomas Coffin <thomas.cof...@artelys.com> wrote: > Hello, > > I have an SVM model previously calibrated using libsvm R implementation from > the e1071 package. > I would like to use this SVM to predict values, from a Java program. > I first tried to use jlibsvm and the "standard" java implementation of > libsvm, without success. > Thus, I am now considering writing data in files from my Java code, calling > an R program to predict values, then gather the predicted values in Java. > > The problem is that I do not know how to re-use the model saved using the > write.svm() function, since there is no read.svm() function. > I read the following message in the mailing archive, stating that I may use > the save and load methods built in R : > http://www.mail-archive.com/r-help@r-project.org/msg64428.html > > Still, I am not sure how to pre-process the data and to post-process the > results. > Since write.svm() writes .scale and .ysale files as well as an svm file, I > figure that the scaling data is included in the svm object. > > Does that mean that I do not have to worry about scaling my data and > unscaling the results provided by the predict function on a model reloaded > using save/load ? > I am asking this because I previously succeeded in loading the svm model > from libsvm in Java, but the results using unscaled data were obviously > wrong.
I think you'll find it helpful (and enlightening) to peruse the source code of the svm stuffs in e1071. Start with the `svm.default` function: you'll see where the scale attributes are calculated (and stored) in the returned object. Then take a peak at the `predict.svm` function. You'll find if and when any scaling is performed on the `newdata` object you are trying to predict labels on. In short, things should "just work" if you save/load the svm object you've previously learned as long as your `newdata` object maintains the same structure your training data had (number and type of features (and column names if you're using the formula interface, I guess)). HTH, -steve -- 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.
