Graphics Reference
In-Depth Information
NOTE
Inkscape might have some issues with fonts as well. You may have noticed that the fonts in
Figure 14-1
don't look quite right. This is because Inkscape (version 0.48) couldn't find Helvetica, and substituted
the font Bitstream Vera Sans instead. A workaround is to copy the Helvetica font file to your personal
font library. For example, on Mac OS X, run
cp /System/Library/Fonts/Helvetica.dfont
~/Library/Fonts/
from a Terminal window to do this, then, when it says there is a font conflict, click
“Ignore Conflict.” After this, Inkscape should properly display the Helvetica font.
Outputting to Bitmap (PNG/TIFF) Files
Problem
You want to create a bitmap of your plot, writing to a PNG file.
Solution
There are two ways to output to PNG bitmap files. One method is to open the PDF graphics
device with
png()
, make the plots, then close the device with
dev.off()
. This method works
for most graphics in R, including base graphics and grid-based graphics like those created by
ggplot2 and lattice:
# width and height are in pixels
png(
"myplot.png"
, width
=
400
, height
=
400
)
# Make plot
plot(mtcars$wt, mtcars$mpg)
dev.off()
For outputting multiple plots, put
%d
in the filename. This will be replaced with 1, 2, 3, and so
on, for each subsequent plot:
# width and height are in pixels
png(
"myplot-%d.png"
, width
=
400
, height
=
400
)
plot(mtcars$wt, mtcars$mpg)
print(ggplot(mtcars, aes(x
=
wt, y
=
mpg))
+
geom_point())
dev.off()
Notice that we called
print()
on the
ggplot
object to make sure that it will be output even
when this code is in a script.
