R help - Mar 2009 - Ggplot2: saving a grid with multiple plots

Hi all,

I have managed to create a figure on the screen with multiple plots in
it. Something like the example below. When I save that with ggsave(),
only the last plot gets saved (pPath in the example) instead of the
entire figure. Any suggestions how I can save this kind of figures
automated?

Thanks,

Thierry

library(ggplot2)
pPoint <- qplot(unemploy/pop, psavert, data=economics)
pPath <- qplot(unemploy/pop, psavert, data=economics, geom="path")
grid.newpage()
pushViewport(viewport(layout = grid.layout(2, 1)))
print(pPoint, vp = viewport(layout.pos.row = 1, layout.pos.col = 1))
print(pPath, vp = viewport(layout.pos.row = 2, layout.pos.col = 1))
ggsave(filename = "test.pdf")

------------------------------------------------------------------------
----
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature
and Forest
Cel biometrie, methodologie en kwaliteitszorg / Section biometrics,
methodology and quality assurance
Gaverstraat 4
9500 Geraardsbergen
Belgium 
tel. + 32 54/436 185
Thierry.Onkelinx at inbo.be 
www.inbo.be 

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ensure that a reasonable answer can be extracted from a given body of
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ONKELINX, Thierry <Thierry.ONKELINX <at> inbo.be> writes:
> I have managed to create a figure on the screen with multiple plots in
> it. Something like the example below. When I save that with ggsave(),
> only the last plot gets saved (pPath in the example) instead of the
> entire figure. Any suggestions how I can save this kind of figures
> automated?
No idea what the easiest way would be if you want both window and 
pdf.

Dieter

library(ggplot2)
pPoint <- qplot(unemploy/pop, psavert, data=economics)
pPath <- qplot(unemploy/pop, psavert, data=economics, geom="path")

pdf(file="test.pdf")
pushViewport(viewport(layout = grid.layout(2, 1)))
print(pPoint, vp = viewport(layout.pos.row = 1, layout.pos.col = 1))
print(pPath, vp = viewport(layout.pos.row = 2, layout.pos.col = 1))
dev.off()