[R] help with tapply and weighted.mean

Hello! I have data frame with 'weights' in one of the columns. I need to compute weighted mean on another column other factor variable and i am trying to: res<-tapply(data$k,list(data$model),weighted.mean,w=data$w,na.rm=T) and i get: Warning messages: 1: longer object length is not a

[R] problems with postscript, lattice and afm

Hello! When i am trying to print lattice plot in postscript file via trellis.device(device=postscript,file='part.eps',family=font1,paper='special',width=16/2.54,height=23/2.54,onefile=FALSE,horizontal=FALSE) everything is ok, but when i am trying to produce multiple files with lattice and trellis.

Re: [R] question about POSIXct conversion

want c("POSIXt", "POSIXct") Try mt <- structure(mt, class=c("POSIXt", "POSIXct")) or mt + ISOdatetime(1970,1,1,0,0,0) or several other such tricks. On Thu, 5 Jun 2003, Kosenkov Kirill wrote: Hello! I am trying to compute minimal time on some

[R] question about POSIXct conversion

Hello! I am trying to compute minimal time on some data like this: mt<-tapply(mrsh$time1,list(mrsh$var1,mrsh$var2),min): a b 145 1054800600 1054789800 340 1054804500 1054794600 349 1054820400 1054792800 55 10548