Datadrames don't have "cells" -- class, type, etc. is determined on a column by column basis (which is the same as a component by component basis, since datframes are also lists) Please read "An Introduction to R" before proceeding and posting so that you understand R's basic data structures and conventions.
BTW -- what do you have against for loops? One should vectorize calculations whenever possible,of course, but for loops are often useful and essentially instantaneous. -- Bert Gunter Genentech Non-Clinical Statistics South San Francisco, CA "The business of the statistician is to catalyze the scientific learning process." - George E. P. Box > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Dave Evens > Sent: Thursday, May 26, 2005 9:31 AM > To: [email protected] > Subject: [R] Q: changing the class of an object > > > Dear All, > > I have a list of dataframes, each cell in every > dataframe (after I have cleaned up the dataframes) is > either real or NA but have class character (I think). > I would like to know how to change the class of every > cell without using a for-loop. I currently have this > > dataframes <- sapply(1: no.of.subs, function(k) > apply(dataframes[[k]], 2, function(x) { > if(class(x)=="character") x <- as(x, "numeric"); x })) > > but this neither changes the cells to numeric nor > keeps the dataframes in a list. > > It creates one dataframe with number of rows=(no of > rows in a dataframe*no of colums) and number of > columns = no.of.subs > > Can someone please help? Thanks in advance for any > help. > > Dave > > ______________________________________________ > [email protected] mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! > http://www.R-project.org/posting-guide.html > ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
