[R] Error in R CMD check 2.8.1

[Michael Friendly]

Env:  R 2.8.1, Win Xp, Eclipse/StatET

In a .Rd file, I have an  example  containing the lines:

# calculate Y M, using polynomial contrasts
trends <- as.matrix(VocabGrowth) %*% poly(8:11, degree=3)
colnames(trends)<- c("Linear", "Quad", "Cubic")

[At the risk of a long message, I'll append the complete .Rd file at the 
end of this message, in case this was
triggered by an error elsewhere.]

I can run R CMD build and R CMD INSTALL without errors, but R CMD check  
terminates with the following
error  -- it seems to treat %*% as a Latex comment.  Can anyone see what 
is wrong?

* checking examples ... ERROR
Running examples in 'heplots-Ex.R' failed.
The error most likely occurred in:

 > ### * VocabGrowth
 >
 > flush(stderr()); flush(stdout())
 >
 > ### Name: VocabGrowth
 > ### Title: Vocabulary growth data
 > ### Aliases: VocabGrowth
 > ### Keywords: datasets
 >
 > ### ** Examples
 >
 > data(VocabGrowth)
 >
 > # Standard Multivariate & Univariate repeated measures analysis
 > Vocab.mod <- lm(cbind(grade8,grade9,grade10,grade11) ~ 1, 
data=VocabGrowth)
 > idata <-data.frame(grade=ordered(8:11))
 > Anova(Vocab.mod, idata=idata, idesign=~grade)
Warning in Anova.mlm(Vocab.mod, idata = idata, idesign = ~grade) :
  the model contains only an intercept: equivalent Type III test substituted

Type III Repeated Measures MANOVA Tests: Pillai test statistic
            Df test stat approx F num Df den Df    Pr(>F)   
(Intercept)  1     0.653  118.498      1     63 4.115e-16 ***
grade        1     0.826   96.376      3     61 < 2.2e-16 ***
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
 >
 > # calculate Y M, using polynomial contrasts
 > trends <- as.matrix(VocabGrowth)
 > colnames(trends)<- c("Linear", "Quad", "Cubic")
Error in dimnames(x) <- dn :
  length of 'dimnames' [2] not equal to array extent
Calls: colnames<-
Execution halted

---- VocabGrowth.Rd ---
\name{VocabGrowth}
\alias{VocabGrowth}
\docType{data}
\title{Vocabulary growth data}
\description{
Data from the Laboratory School of the University  of Chicago. 
They consist of scores from a cohort of pupils in grades 8-11 on
the vocabulary section of the Cooperative Reading Test.  The
scores are scaled to a common, but arbitrary origin and unit
of measurement, so as to be comparable over the four grades.

}
\usage{data(VocabGrowth)}
\format{
  A data frame with 64 observations on the following 4 variables.
  \describe{
    \item{\code{grade8}}{Grade 8 vocabulary score}
    \item{\code{grade9}}{Grade 9 vocabulary score}
    \item{\code{grade10}}{Grade 10 vocabulary score}
    \item{\code{grade11}}{Grade 11 vocabulary score}
  }
}
\details{
Since these data cover an age range in which physical growth
is beginning to decelerate, it is of interest whether a
similar effect occurs in the acquisition of new vocabulary.
}
\source{
  R.D.  Bock,
  \emph{Multivariate statistical methods in behavioral research}, 
McGraw-Hill, New York,
1975, pp453. 
}
\references{
  Keesling, J.W., Bock, R.D. et al, "The Laboratory School study of 
vocabulary growth",
  University of Chicago, 1975.
}
\examples{
data(VocabGrowth)

# Standard Multivariate & Univariate repeated measures analysis
Vocab.mod <- lm(cbind(grade8,grade9,grade10,grade11) ~ 1, data=VocabGrowth)
idata <-data.frame(grade=ordered(8:11))
Anova(Vocab.mod, idata=idata, idesign=~grade)

# calculate Y M, using polynomial contrasts
trends <- as.matrix(VocabGrowth) %*% poly(8:11, degree=3)
colnames(trends)<- c("Linear", "Quad", "Cubic")

within.mod <- lm(trends ~ 1)

Manova(within.mod)
heplot(within.mod, terms="(Intercept)", col=c("red", "blue"), type="3",
    main="HE plot for Grade effect")
points(0,0, cex=2.5, col="green", pch=19)
text(0,0, col="green", pos=2, labels="H0")

}
\keyword{datasets}
--- end ---

-- 
Michael Friendly     Email: friendly at yorku.ca 
Professor, Psychology Dept.
York University      Voice: 416 736-5115 x66249 Fax: 416 736-5814
4700 Keele Street    http://www.math.yorku.ca/SCS/friendly.html
Toronto, ONT  M3J 1P3 CANADA