[GRASSLIST:3015] RE: [gislist] US cities and counties
Martin du Saire
mdusaire at umn.edu
Tue Mar 23 09:59:40 EST 2004
Hello again,
As I mentioned, I am compiling corn yield data for the grain belt US based
on county-wide data for about 14 states. Eventually I will need to plot
these data to analyze yield spatial distribution. So I need to be able to
assign these county production values to some location, probably the
geographic center of each county.
One of the goals is to calculate a center of mass for production. The
region of interest spans:
Lat: 35N to 49N
Lon: -104 to -80
The question is how to choose a projection that will allow me to calculate
a reasonable (yet to be determined what will be considered reasonable)
estimate of center of mass. I am considering Albers Equal Area,
Equidistant Conic, Azimuthal Equidistant, and Two-Point Equidistant. (I am
using GRASS, and I think TPE is not supported).
Thanks again for your help.
Martin
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