Comments on: Projection Parameters / Point-Of-Origin For State Plane Coordinate Systems (SPCS) http://freegeographytools.com/2008/projection-parameters-point-of-origin-for-state-plane-coordinate-systems-spcs Exploring the world of free tools for GIS, GPS, Google Earth, neogeography, and more. Wed, 18 Nov 2009 03:05:04 -0700 http://wordpress.org/?v=2.8.6 hourly 1 By: Andrew Danner http://freegeographytools.com/2008/projection-parameters-point-of-origin-for-state-plane-coordinate-systems-spcs/comment-page-1#comment-1136 Andrew Danner Fri, 09 May 2008 18:45:35 +0000 http://freegeographytools.com/2008/projection-parameters-point-of-origin-for-state-plane-coordinate-systems-spcs#comment-1136 OGR which is part of GDAL recommends the Proj library http://www.remotesensing.org/proj which includes a bunch of projection parameters for state plane in the file /usr/share/proj/epsg (on a Debian/Linux system) including epsg codes For example for North Carolina, # NAD83 / North Carolina (ftUS) +proj=lcc +lat_1=36.16666666666666 +lat_2=34.33333333333334 +lat_0=33.75 +lon_0=-79 +x_0=609601.2192024384 +y_0=0 +ellps=GRS80 +datum=NAD83 +to_meter=0.3048006096012192 +no_defs OGR can convert based on EPSG codes (in this example 2264), which if you have a handful of common projections, it is easier to remember a few epsg codes than wacky projection parameters. OGR which is part of GDAL recommends the Proj library
http://www.remotesensing.org/proj which includes a bunch of projection parameters for state plane in
the file /usr/share/proj/epsg (on a Debian/Linux system) including epsg codes
For example for North Carolina,

# NAD83 / North Carolina (ftUS)
+proj=lcc +lat_1=36.16666666666666 +lat_2=34.33333333333334 +lat_0=33.75 +lon_0=-79 +x_0=609601.2192024384 +y_0=0 +ellps=GRS80 +datum=NAD83 +to_meter=0.3048006096012192 +no_defs

OGR can convert based on EPSG codes (in this example 2264), which if you have a handful of common projections, it is easier to remember a few epsg codes than wacky projection parameters.

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