[Rd] Notes on bug reports 3229 and 3242 - as.matrix.data.fram e

Gorjanc Gregor Gregor.Gorjanc at bfro.uni-lj.si
Fri Feb 11 21:36:48 CET 2005

From: Liaw, Andy [mailto:andy_liaw at merck.com]
> From: Gorjanc Gregor

> ! Yes, I was not able to do it from my data. But bellow is one. It is
> ! a stupid one, but it works. The problem is use of as.data.frame in 
> ! tmp1$L <- as.data.frame(tmp$L). This looks like to produce 
> a corrupted
> ! data.frame. If I use just tmp1$L <- tmp$L, write.table and 
> ! as.matrix.data.frame works OK. I still think that mine proposal can
> ! give benefit, since it works also on corrupted data frames.
> data(warpbreaks)
> tmp <- as.data.frame(tapply(breaks, list(wool, tension), mean))
> tmp1 <- data.frame(level=rownames(tmp))
> tmp1$L <- as.data.frame(tmp$L)

Here's the problem that Brian is referring to:  Why do you make one variable
in the data frame a data frame?  That's what caused problem in

! I agree completely and as I have described up it is my fault that
! I have/had problems with as.matrix.data.frame by use of write.table.
! But I think that my proposal is nice, since as.matrix.data.frame would 
! be more robust.

! With regards, Gregor

More information about the R-devel mailing list