#################################################################################### We have used maptools to construct state, county, township, census-tract, and zipcode level R maps with an Albers Conical Equal Area projection. We would like to be able to plot the location of weather stations or other point locations on the maps. The data the point locations are in latitude-longitude units and we must convert the coordinates to the Albers Conical Equal Area coordinates.
However, as of yet, we have not been able to obtain satisfactory results using mapproj. Given the specs below can someone please tell us how to use mapproj (or some other R library) to convert lat-long coordinates into the appropriate Albers Conical Equal Area coordinates? Thanks in advance Joe Atwood Montana State University [EMAIL PROTECTED] #################################################################################### The material at the bottom of this message is the metadata from the shapefile we are using (as created in Arc-GIS). #################################################################################### ----------------------------------- Horizontal coordinate system Projected coordinate system name: NAD_1927_Albers Geographic coordinate system name: GCS_North_American_1927 Details Map Projection Name: Albers Conical Equal Area Standard Parallel: 29.500000 Standard Parallel: 45.500000 Longitude of Central Meridian: -96.000000 Latitude of Projection Origin: 23.000000 False Easting: 0.000000 False Northing: 0.000000 Planar Coordinate Information Planar Distance Units: meters Coordinate Encoding Method: coordinate pair Coordinate Representation Abscissa Resolution: 0.008192 Ordinate Resolution: 0.008192 Geodetic Model Horizontal Datum Name: North American Datum of 1927 Ellipsoid Name: Clarke 1866 Semi-major Axis: 6378206.400000 Denominator of Flattening Ratio: 294.978698 _________________ Bounding coordinates Horizontal In decimal degrees West: -127.889829 East: -65.349890 North: 51.606167 South: 22.862978 In projected or local coordinates Left: -2356341.706499 Right: 2257925.009693 Top: 3172647.320063 Bottom: 268329.067476 ################################################################################### ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
