W.R.T. multiple pages, the HELP page says to use a filename like this:
png(filename = "Rplot%03d.png",
where %03d is an incremented value for each page.
On Fri, Jan 2, 2009 at 2:23 PM, Mike Williamson <this.is.mvw at gmail.com>
wrote:> Hello all and thanks in advance for any help,
>
> There are really two issues that I am having, both related to saving
> graphs:
> 1) It seems that the "dev...()" functions are unstable when using
higher
> level graphs (specifically I was using levelplot)
>
> 2) I have a large grid of levelplot graphs that I can print out into a
> subset quite easily when I print to screen, but if I print to a file, I
> cannot print the subset. (I mention .png in the subject because that's
what
> I used, but really any format is acceptable to me).
>
> ========================================================>
> 1) Unstable dev...() functions:
>
>
> I have the following line of code embedded in a function using simple
"plot"
> commands and it works fine:
>
> if(!is.na(plotFileName)) dev.off()
>
> I set "plotFIleName" as "NA" by default, in which
case the plot prints
> to screen. If a name is given, the print goes to the png() function.
> Therefore, I want to turn the device off to ensure that the next plot
isn't
> sent to the same device & overwrites it.
> This works *perfectly fine* when using the plot function. This exact
> same code, however, does not work for levelplot or (I am assuming) any
other
> higher level trellis (sp!) graphs. Below are snippets of the entire code,
> edited a bit for
>
> if(!is.na(plotFileName)) {
> print(paste("Saving Zonal plot to file
",plotFileName,".png",sep=""))
> print("(To display instead, do not pass any 'plotFileName'
argument to
> cro.zone.plot function.)")
> maxLayout <- c(0,length(unique(miniDataSet$splitCol)))
> png(filename >
paste(as.character(plotFileName),".png",sep=""),width=(1.2*plotSize*(maxLayout[2]^(1/3))),
> height=(plotSize*(maxLayout[2]^(1/3))))
> } else {
> devAskNewPage(ask = TRUE)
> maxLayout <- c(0,min(16,length(unique(miniDataSet$splitCol))))
> }
> levelplot(dataCol ~ siteX * siteY | splitCol,data = miniDataSet,
>
>
col.regions=rainbow(n=length(unique(miniDataSet$dataCol))+5,start=0.5,end=0.95),
> layout = maxLayout,
> shrink = c(0.6,1.1),at >
keyCols,xlab=list(label=xlab,cex=labelScale),
> ylab=list(label=ylab,cex=labelScale),scales >
list(cex=axisScale),
> main=list(label=paste(dataCol,plotTitle,splitCol),
> cex=titleScale),colorkey=list(labels=list(cex=labelScale)))
>
> if(!is.na(plotFileName)) dev.off()
>
> If I keep the code exactly as is, it will not work. If I remove *just the
> last line*, the function will work, and then I simply have to manually
> remove the device "by hand" (also by using dev.off() ) outside of
the
> function code. Now the *really weird* thing: if I comment out that last
> "if(!is.na... dev.off()" line, the function *still does not
work*. I
> literally have to remove the line, I cannot simply comment it out! This is
> why I think it is "unstable".
> I have found a way around this (I simply put a loop in the front of any
> of my plotting functions to ensure they have turned off all devices before
> doing anything... this seems to work), so this is not my biggest problem,
> personally. But it does seem to be a bigger problem for R itself, and for
> this community.
> On a related note: I have noticed that sometimes
"devAskNewPage(ask > TRUE)" is also buggy. Normally I can just
alter the code slightly to get it
> to work, but the solutions are odd. (For instance, I have found that if
> "devAskNewPage(ask = TRUE)" is in an "if" clause, it
sometimes won't work
> unless I use the { } brackets around it, even with a one line if clause.
>
> =======================================>
> 2) Printing multiple pages to png:
>
> If you look through the code above, you'll see that I have altered the
size
> of the grid that is printed, depending upon whether it is printed to screen
> or to png. Specifically, look at:
>
> if(!is.na(plotFileName)) {
> ...
> maxLayout <- c(0,length(unique(miniDataSet$splitCol)))
> ...
> } else {
> ...
> maxLayout <- c(0,min(16,length(unique(miniDataSet$splitCol))))
> }
> levelplot(...layout = maxLayout...)
>
> The reason I do this is because when I print to screen, the
"askNewPage"
> will allow me to look at the screen before the next one is printed. I
could
> even screen capture that, if I wanted to choose a slow, ugly, and
> non-scriptable solution. But if I try to send to png, each of the new
pages
> of the grid overwrite each other.
> Specifically, this levelplot is making a grid of ~ 60 graphs. Since the
> layout maxes to 16 graphs per page, it nicely forces it to a 4 x 4 matrix
of
> graphs, 4 pages long. For the visual display, this is fine, as I mention.
> For the save to png, only one of the pages is captured. And, oddly, it is
> rarely the last page. I don't quite understand this, but it is usually
> either the 2nd or the 3rd page that is saved to the png.
> You can see my solution to it in the code above: when saving to png,
> all of the graphs are printed out in a gigantic grid, but I also increase
> the height & width of the graph set so that each individual plot
isn't too
> tiny. It isn't a totally useless solution, but still not ideal.
>
> I think I just don't quite understand how to use these
"devices", as
> they are called, and that is the root of the problem. In fact, I don't
even
> know how to bring one device (say, for instance, the device holding the png
> graph) to another device type. E.g., a solution I was trying to figure out
> was to simply print everything to screen and then switch the screen device
> to png. This still isn't ideal because it requires constant user
> interaction, but it nonetheless illuminated the fact that I don't
understand
> how to manage the devices.
>
> Thanks in advance for any help!
> Mike
>
> [[alternative HTML version deleted]]
>
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> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
--
Jim Holtman
Cincinnati, OH
+1 513 646 9390
What is the problem that you are trying to solve?
