R 3.2.0
OS X
Colleagues
I have a script that has been unchanged for years but I just noticed a
difference in the output. A minimal example is:
jpeg(file="xxx.jpeg", width=4, height=2, unit="in",
pointsize=12, bg="white", res=150, quality=100)
plot(1)
graphics.off()
system("open xxx.jpeg") ## works in OS X -- use 'start'
instead of 'open' in Windows
In the past (probably more than several months ago, although I can?t identify
when the change occurred), this yielded a graphic that appears to be the
intended size (4 x 2). I assess this based on the size on the screen and the
size when I drag the file to a Word document.
With R 3.2.0 (and 3.1.3), the image is appreciably larger, i.e., the width and
height options appear to be ignored.
OS X?s Preview application includes an inspector that provided information about
the images.
In the earlier incarnations, Inspector reported that the image has 150 pixels /
inch. With 3.2.0, it shows 72 pixels / inch.
I think that the problem is as follows ? the image is created with the correct
number of pixels ? but the info as to pixels / inch is not being handled
correctly.
I can confirm this by replacing
res=150
with
res=72
The resulting image is the intended size.
Is this a bug? The workaround appears to be restoring res=72 but that does not
seem to be an ideal solution.
Dennis
Dennis Fisher MD
P < (The "P Less Than" Company)
Phone: 1-866-PLessThan (1-866-753-7784)
Fax: 1-866-PLessThan (1-866-753-7784)
www.PLessThan.com