I want the column that is never going to actually have the '(all)' level to not become of type factor. continuing the example:
chick_m$diet = as.integer(as.character(chick_m$diet)) is.factor(chick_m$diet) #returns FALSE is.factor(cast(subset(chick_m, time == 0), diet + chick ~ time, mean, margins="diet")$diet) #returns TRUE does that make sense? the way it works now, it totally screws things up when the column for which you get margins is not a factor. in my case, a date column. thanks, Mike hadley wrote: > > On Wed, Jul 30, 2008 at 11:47 AM, mfrumin <[EMAIL PROTECTED]> wrote: >> >> according to the documentation of the cast function in the reshape >> function, >> I would expect this bit of code from the examples to calculate marginal >> means over only the 'diet' variable. >> >> #Chick weight example >> names(ChickWeight) <- tolower(names(ChickWeight)) >> chick_m <- melt(ChickWeight, id=2:4, na.rm=TRUE) >> cast(chick_m, diet + chick ~ time, mean, margins="diet") >> >> But, >> summary(cast(subset(chick_m, time == 0), diet + chick ~ time, mean, >> margins="diet")) returns: >> >> diet chick 0 >> 1 :21 (all) : 4 Min. :39.00 >> 2 :11 18 : 1 1st Qu.:40.85 >> 3 :11 16 : 1 Median :41.00 >> 4 :11 15 : 1 Mean :41.05 >> (all): 0 13 : 1 3rd Qu.:42.00 >> 9 : 1 Max. :43.00 >> (Other):45 >> >> which shows that it calculated margins on the 'chick' column as well. >> this >> behavior causes great problems for me when in my data one of the columns >> is >> a non-factor column, eg a Date, but the unrequested margining behavior >> turns >> that column into a factor. >> >> am I missing something? > > Hi Mike, > > I'm not sure what you want - if you want margins at the diet level, > then you have to margin over all of the chicks at that level, which is > then displayed as (all). Maybe you want margin = "grand_row" ? > > Hadley > > > -- > http://had.co.nz/ > > ______________________________________________ > 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. > > -- View this message in context: http://www.nabble.com/bug-in-%27margins%27-behavior-in-reshape---cast-tp18737649p18738699.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.
