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Click here to see the example.
This one was a "long time coming" :-)
For many years, I had always wanted to try to do a sas/graph version
of the US map shown in Calvin Schmid's book "Statistical Graphics -
Design Principles and Practices" with globe-shaped markers ... and,
I finally figured out a way to do it :)
In the past, I had used annotate to put round/circular markers (or pies)
on a map, but they were strictly 2d in their look. In those examples, I
made the "area" of the circular markers proportional to the data values.
But when you have really large values in one state, and relatively small
values in another state, the larger pies completely dwarf the smaller ones.
If you can use 3d spheres, and let the values be proportional to the
*volume* of the spheres, then the larger and smaller values co-exist
in a little better harmony on the same map.
Since SAS/Graph gmap doesn't have any built-in 3d sphere marker capability,
I used annotate. I basically took some code that I had used to annotate
long/lat gridlines on a world map, and I then took that annotate dataset
and projected it into a round globe-looking thing, and scaled it down to
a much smaller size (the exact size/volume of the spheres being determined
by the data).
Remember, the equation for the volume of a sphere is ... 4/3 * pie * r^3
Also, I use the annotate's html variable's "title" to code in some
charttip/flyover-text, so you can mouse over the globe-shaped markers
and see the detailed data.
And then I annotate a bunch of text labels, for all the stuff other than
the titles and footnotes.
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