----- Original Message ----- From: "Petr PIKAL" <[EMAIL PROTECTED]> To: "sun" <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Sent: Wednesday, October 24, 2007 4:46 PM Subject: Re: [R] convert factor dataframe into numeric matrix
> Hi > > [EMAIL PROTECTED] napsal dne 24.10.2007 16:24:29: > >> >> ----- Original Message ----- >> From: "Prof Brian Ripley" <[EMAIL PROTECTED]> >> To: "sun" <[EMAIL PROTECTED]> >> Cc: <[EMAIL PROTECTED]> >> Sent: Wednesday, October 24, 2007 2:58 PM >> Subject: Re: [R] convert factor dataframe into numeric matrix >> >> >> > On Wed, 24 Oct 2007, sun wrote: >> > >> >> Bear me if this is a naive question. >> >> >> >> I have a dataframe, all lists inside it are factors. When I use >> > >> > Do you mean 'all columns are factors'? A data frame is a list but > usually >> > does not contain lists. >> > >> >> as.matrix(df) to convert, I get a character matrix while my intention > is >> >> to >> >> get numeric matrix. I can make the convertion iteratively by each > list >> >> but >> >> I do think there is some more elegant way of doing this. >> >> >> >> please let me know if I missed somthing there. >> > >> > ?data.matrix may be what you are looking for: you gave us too little >> > detail to be sure. >> > >> >> >> Thanks for your helps. I did not provide data 'cause I thought this is > FAQ >> type of question(maybe wrong impression). >> Actually I use algdesign generated a factorial design data frame in > which: >> > >> > str(dat) >> 'data.frame': 2304 obs. of 6 variables: >> $ party : Factor w/ 3 levels "1","2","3": 1 2 3 1 2 3 1 2 3 1 ... >> $ dinner: Factor w/ 3 levels "1","2","3": 1 1 1 2 2 2 3 3 3 1 ... >> $ d1 : Factor w/ 4 levels "1","2","3","4": 1 1 1 1 1 1 1 1 1 2 ... >> $ p1 : Factor w/ 4 levels "1","2","3","4": 1 1 1 1 1 1 1 1 1 1 ... >> $ d2 : Factor w/ 4 levels "1","2","3","4": 1 1 1 1 1 1 1 1 1 1 ... >> $ p2 : Factor w/ 4 levels "1","2","3","4": 1 1 1 1 1 1 1 1 1 1 ... >> >> I just figured out a way fo convert it to numeric matrix using >> >d = as.data.frame(lapply(dat,as.numeric)) >> >> but "data.matrix()" suggested by Prof. Brian and Mr. Dimitris is exactly > the >> thing I was looking for. >> >> I am not sure if there exist some documents or online source that have >> documented these kind of "utility functions" categorized in somet > categories >> like "data types", "data manipulating functions", "variable scopes", > etc., >> that allow a quick browsing for some functions or other information. >> > > Try to look at Paul Johnson's StatsRus pages, which provide a collection > of HowTo's. And maybe introduction to R manual in doc directory. > > Regards > Petr > this page is enormously helpful and I like the way it was organized, Thanks very much for the link. Best, Sun ______________________________________________ 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.