prj - Projection Information (Guile Shapefile)

1.3 prj - Projection Information

Module (shapefile prj).

The prj files contains information about the map projection.

For example ²

PROJCS["SWEREF99_TM",GEOGCS["GCS_SWEREF99",DATUM["D_SWEREF99",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",15.0],PARAMETER["Scale_Factor",0.9996],PARAMETER["Latitude_Of_Origin",0.0],UNIT["Meter",1.0]]

Which pretty printed becomes.

PROJCS[
	"SWEREF99_TM",
	GEOGCS[
		"GCS_SWEREF99",
		DATUM["D_SWEREF99",SPHEROID["GRS_1980",6378137.0,298.257222101]],
		PRIMEM["Greenwich",0.0],
		UNIT["Degree",0.0174532925199433]
	],
	PROJECTION["Transverse_Mercator"],
	PARAMETER["False_Easting",500000.0],
	PARAMETER["False_Northing",0.0],
	PARAMETER["Central_Meridian",15.0],
	PARAMETER["Scale_Factor",0.9996],
	PARAMETER["Latitude_Of_Origin",0.0],
	UNIT["Meter",1.0]
]

The parser currently only handles the compact version, and produces the following S-expression.

(PROJCS
  "SWEREF99_TM"
  (GEOGCS
    "GCS_SWEREF99"
    (DATUM "D_SWEREF99"
           (SPHEROID "GRS_1980" 6378137.0 298.257222101))
    (PRIMEM "Greenwich" 0.0)
    (UNIT "Degree" 0.0174532925199433))
  (PROJECTION "Transverse_Mercator")
  (PARAMETER "False_Easting" 500000.0)
  (PARAMETER "False_Northing" 0.0)
  (PARAMETER "Central_Meridian" 15.0)
  (PARAMETER "Scale_Factor" 0.9996)
  (PARAMETER "Latitude_Of_Origin" 0.0)
  (UNIT "Meter" 1.0))

Function: parse-prj-file port: Reads projection data from port, returing sexp as above.

Footnotes

(2)

Data from Lantmäteriet, See Lantmäteriet