[R-sig-Geo] anyone with experience with maptools and Census TIGER shapefiles: Massachusetts plots bizarrely

Andrew Yee yee at post.harvard.edu
Mon Mar 21 03:02:30 CET 2011


Two questions:

1. I was wondering if anyone has thoughts about the shapefiles from
the U.S. Census.  Specifically, I'm interested in plotting an outline
of Massachusetts.  I downloaded the "state and equivalent" shapefile
for Massachusetts from
http://www2.census.gov/cgi-bin/shapefiles2009/state-files?state=25.

map <- readShapeSpatial('tl_2009_33_state.shp')
plot(map)

renders a very bizarre looking Massachusetts, with the Cape looking like a blob.

2. On the other hand, if you download a shapefile from here:

http://pubs.usgs.gov/of/2009/1072/GIS/shapefile/OUTLINE25K_POLY.zip

this renders something that looks appropriate.  However, the
coordinates are not in latitude or longitude.  Is there a method for
obtaining these coordinates in latitude and longitude from this
shapefile?

(Note I'm familiar with the maps package, but was looking for a higher
resolution coastline).

Thanks,
Andrew



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