[R] Conflict between xtable and Hmisc when using Sweave?

[Sander Oom]

Dear R users,

The Sweave code below runs fine, as it is. However, an error occurs when 
the line 'library(xtable)' is uncommented:
Error:  chunk 1
Error in "label<-"(`*tmp*`, value = "month") :
         no applicable method for "label<-"

Is anybody aware of this and knows a workaround?

Thanks,

Sander.

*******************

\documentclass[a4paper]{article}
\title{Sweave Test for summarize}
\author{Sander Oom}

\usepackage{a4wide}

\begin{document}

\maketitle

\begin{figure}[ht]
\begin{center}
<<fig=TRUE,echo=FALSE>>=
   # library(xtable)
   library(Hmisc)
   set.seed(111)
   dfr <- expand.grid(month=1:12, year=c(1997,1998), reps=1:100)
   month <- dfr$month
   year <- dfr$year
   y <- abs(month-6.5) + 2*runif(length(month)) + year-1997
   s <- summarize(y, llist(month,year), smedian.hilow, conf.int=.5)
   print(xYplot(Cbind(y,Lower,Upper) ~ month, groups=year, data=s,
         keys='lines', method='alt', type='b'))
@
\end{center}
\end{figure}

\end{document}

************************



 > version
          _
platform i686-pc-linux-gnu
arch     i686
os       linux-gnu
system   i686, linux-gnu
status
major    2
minor    1.0
year     2005
month    04
day      18
language R


-- 
--------------------------------------------
Dr. Sander P. Oom
Animal, Plant and Environmental Sciences,
University of the Witwatersrand
Private Bag 3, Wits 2050, South Africa
Tel (work)      +27 (0)11 717 64 04
Tel (home)      +27 (0)18 297 44 51
Fax             +27 (0)18 299 24 64
Email   sander at oomvanlieshout.net
Web     www.oomvanlieshout.net/sander