R help - Oct 2003 - win.metafile() problem -- possible bug?

As a followup to a previous posting regarding the win.metafile()
function, I've been having some problems as well.  In my case, I've been
converting some scripts from S-SPLUS to R that create graphs in order to
take advantage of R's plotmath capabilities.

In the sample code shown below, the axis labels display the units for
the data.  In particular, the units for the y axis are "grams carbon per
meter squared per month" or "gC m-2 m-1".  I have noticed that
using the
following code, if one prints directly from the graph window, the plot
prints correctly with the proper spacing between the "gC",
"m-2", and
"m-1".  However, when I use either the "copy as metafile"
feature of the
Windows RGui or add a direct call to win.metafile(), the subsequent .wmf
file does not have spaces between the components of the axis labels.

#win.metafile(filename= "Rplot%02d.emf", height=11, width=8.5,
pointsize=12)
par(mar= c(5,4,4,5)+0.1)

x <- 1:10
y <- 0.8*x+1
plot(x, y, type="n", axes=F, xlab="", ylab="")
box()
points(x, y, pch=1, col=1, cex=1.2)
axis(side=2)
mtext(side=2, line=2.5, expression(paste("monthly (gC ", m^-2, "
",
m^-1, ")")))
axis(side=1, at=1:12)

par(new=T)#, xaxs="d")
plot(x, y, type="n", axes=F, xlab="", ylab="")
y <- 0.5*x-1
points(x, y, pch=16, col=1, cex=1.2)
axis(side=4)
mtext(side=4, line=3, expression(paste("cumulative (gC ", m^-2,
")")))


I have been working with R 1.8.0 on a computer runing Windows XP.
However, I've also tried the code under R 1.7.1, and the behavior
appears to be the same.  Also, the "correct" spacing when printing the
graph window directly does not appear to be related to what kind of
print driver is used because both PostScript and PCL drivers print
correctly.  Moreover, I've also tried to paste the metafile into a
program other than MS Word, but the results are the same as with MS
Word.  So I am guessing that the lack of spaces between the axis label
components is related to the creation of the windows metafile.

A workaround is that an extra space can be added in the call to
expression(), but it certainly would be nice not to need two different
statements that depended on whether the graph was printed directly or
saved as a metafile.

So could this be a bug, or is it some sort of known limitation when
creating metafiles?

Thanks for your time and consideration,

-Paul Schwarz

Dear R experts,


I have been trying to run an iterative procedure in R and am having
some sort of memory build up problem. I am using R1.8.0 on Windows XP.
One single iteration of my procedure is coded into a function. This
function creates an extremely large matrix of simulated values (actually
calls WinBugs which returns simulations), does some calculations with it
and returns a single number as a result.  After this one step I no longer
need this large matrix but it seems to be stored in memory anyhow. The
code is something like:


	parameter <- 0 # initial value
	for  (i in 1:1000)
		{
		parameter <- one.step(parameter, data)
		mem <- memory.size()
		cat(parameter," ", mem,"\n")
		}


I output the memory.size() at each iteration and this grows and grows 
until I run out of memory and get an allocation error. When this happens,
I record the last parameter value, quit R, start R again and rerun the
procedure starting with this most recent value. I'd rather not do it this
way! I have increased the memory limit using the memory.limit() function
and this helps a bit. 

My Questions:

1. Is there any way to free the memory after each iteration since 
I really don't need anything other than the most recent parameter value?

2. If I run this code on the same machine but using the Linux OS will i
have the same problem?

3. Would I be able to avoid this problem if I ran the loop in some other
language like Perl or C and called the R function to do one iteration at
each step.  

I have noticed several postings about this sort of thing in the archives
but I'm still a bit unclear. Any help is greatly appreciated.

Thanks,
Farouk