Hello wizards, I need to convert the following functions (prestd, poststd, prepca) of matlab to R. Does Somebody knows how to do it. A description of the functions is: prestd preprocesses the network training set by normalizing the inputs and targets so that they have means of zero and standard deviations of 1. poststd postprocesses the network training set which was preprocessed by prestd. It converts the data back into unnormalized units. prepca preprocesses the network input training set by applying a principal component analysis. This analysis transforms the input data so that the elements of the input vector set will be uncorrelated. In addition, the size of the input vectors may be reduced by retaining only those components which contribute more than a specified fraction (min_frac) of the total variation in the data set. Thanks in advance.
Hi check out R-and-octave.txt on the contributed docs section of CRAN. HTH Robin On 28 Aug 2006, at 17:50, Lord Tyranus wrote:> Hello wizards, I need to convert the following functions (prestd, > poststd, prepca) of matlab to R. Does Somebody knows how to do it. A > description of the functions is: > > prestd preprocesses the network training set by normalizing the inputs > and targets so that they have means of zero and standard deviations of > 1. > > poststd postprocesses the network training set which was preprocessed > by prestd. It converts the data back into unnormalized units. > > prepca preprocesses the network input training set by applying a > principal component analysis. This analysis transforms the input data > so that the elements of the input vector set will be uncorrelated. In > addition, the size of the input vectors may be reduced by retaining > only those components which contribute more than a specified fraction > (min_frac) of the total variation in the data set. > > Thanks in advance. > > ______________________________________________ > R-help at stat.math.ethz.ch 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.-- Robin Hankin Uncertainty Analyst National Oceanography Centre, Southampton European Way, Southampton SO14 3ZH, UK tel 023-8059-7743
Hi On 28 Aug 2006 at 10:50, Lord Tyranus wrote: Date sent: Mon, 28 Aug 2006 10:50:15 -0600 From: "Lord Tyranus" <lord.tyranus.96 at gmail.com> To: r-help at stat.math.ethz.ch Subject: [R] Help with Functions> Hello wizards, I need to convert the following functions (prestd, > poststd, prepca) of matlab to R. Does Somebody knows how to do it. A > description of the functions is: > > prestd preprocesses the network training set by normalizing the inputs > and targets so that they have means of zero and standard deviations of > 1.Maybe scale function> > poststd postprocesses the network training set which was preprocessed > by prestd. It converts the data back into unnormalized units.work with attributes of scaled values. HTH Petr> > prepca preprocesses the network input training set by applying a > principal component analysis. This analysis transforms the input data > so that the elements of the input vector set will be uncorrelated. In > addition, the size of the input vectors may be reduced by retaining > only those components which contribute more than a specified fraction > (min_frac) of the total variation in the data set. > > Thanks in advance. > > ______________________________________________ > R-help at stat.math.ethz.ch 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.Petr Pikal petr.pikal at precheza.cz