Question on big JPG plots in function warpping format

Most likely this is FAQ 7.22.

althogh how we are supposed to know what plotHeatTrellis does is beyond 
me.

On Fri, 10 Feb 2006, alexfang at stat.rutgers.edu wrote:

Hello:

I have problems generating big JPG plots in functions.  the following code runs
fine in the script:

#### runs fine in script, generate 40k "test1.jpg" in the given directory
plotPlatesAlong <- c(1:5)
plotDirPath <- paste(dataPath, "OutputPlots\\", sep="")
filename <-   paste(plotDirPath,"test1.jpg", sep="")
jpeg(file=filename)
plotHeatTrellis(dataPath, plotVariable = "Raw", plotPlatesAlong)
   # here plotHeatTrellis() generates a complicate plot, but it works
dev.off()
#### End of script


but if I wrap it in a function, it doesn't work.

######## put it in a function and run test(dataPath)
######## it will make "test1.jpg" in the given directory, but only 6k in size
######## and if I open the file, it's blank
test <- function(dataPath) {
plotPlatesAlong <- c(1:5)
plotDirPath <- paste(dataPath, "OutputPlots\\", sep="")
filename <-   paste(plotDirPath,"test1.jpg", sep="")
jpeg(file=filename) #
plotHeatTrellis(dataPath, plotVariable = "Raw", plotPlatesAlong)
dev.off()
}
######### enf of the program


I've tested the simple plot function, like

########## works fine both with in script and function wrapping format
testplot <- function(plotDirPath) {
filename1 <- paste(plotDirPath, "test1.jpg",sep="")
jpeg(file=filename1)
plot(1:10, rnorm(10, 0), type="b")
dev.off()
}
###########

Any one have any clues, why this happen and how could I fix my code and my mine
working also in the function wrapping format?  Thanks.


best, Alex

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
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