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GEODESICPROJ(1) 	     GeographicLib Utilities		 GEODESICPROJ(1)

NAME
     GeodesicProj -- perform projections based on geodesics

SYNOPSIS
     GeodesicProj  ( -z | -c | -g ) lat0 lon0 [ -r ] [ -e a f ] [ -w ] [ -p prec
     ] [ --comment-delimiter commentdelim ] [ --version | -h | --help ] [  --in-
     put-file  infile | --input-string instring ] [ --line-separator linesep ] [
     --output-file outfile ]

DESCRIPTION
     Perform projections based on geodesics.  Convert  geodetic  coordinates  to
     either  azimuthal	equidistant,  Cassini-Soldner,	or gnomonic coordinates.
     The center of the projection (lat0, lon0) is specified by either the -c op-
     tion (for Cassini-Soldner), the -z option (for azimuthal  equidistant),  or
     the  -g option (for gnomonic).  At least one of these options must be given
     (the last one given is used).

     Geodetic coordinates are provided on standard input as a set of lines  con-
     taining  (blank  separated)  latitude and longitude (decimal degrees or de-
     grees, minutes, seconds); for details on the allowed formats  for	latitude
     and  longitude,  see the "GEOGRAPHIC COORDINATES" section of GeoConvert(1).
     For each set of geodetic coordinates, the corresponding  projected  coordi-
     nates  x,	y  (meters) are printed on standard output together with the az-
     imuth azi (degrees) and reciprocal scale rk.  For Cassini-Soldner,  azi  is
     the bearing of the easting direction and the scale in the easting direction
     is  1  and  the  scale  in  the  northing direction is 1/rk.  For azimuthal
     equidistant and gnomonic, azi is the bearing of the  radial  direction  and
     the  scale  in  the azimuthal direction is 1/rk.  For azimuthal equidistant
     and gnomonic, the scales in the radial direction are 1 and 1/rk^2,  respec-
     tively.

OPTIONS
     -z lat0 lon0
	 use  the  azimuthal equidistant projection centered at latitude = lat0,
	 longitude = lon0.  The -w flag can be used to swap the default order of
	 the 2 coordinates, provided that it appears before -z.

     -c lat0 lon0
	 use the Cassini-Soldner projection centered at latitude = lat0,  longi-
	 tude  = lon0.	The -w flag can be used to swap the default order of the
	 2 coordinates, provided that it appears before -c.

     -g lat0 lon0
	 use the ellipsoidal gnomonic projection centered at  latitude	=  lat0,
	 longitude = lon0.  The -w flag can be used to swap the default order of
	 the 2 coordinates, provided that it appears before -g.

     -r  perform  the  reverse	projection.  x and y are given on standard input
	 and each line of standard output gives latitude,  longitude,  azi,  and
	 rk.

     -e a f
	 specify  the ellipsoid via the equatorial radius, a and the flattening,
	 f.  Setting f = 0 results in a sphere.  Specify f < 0 for a prolate el-
	 lipsoid.  A simple fraction, e.g., 1/297, is allowed  for  f.	 By  de-
	 fault, the WGS84 ellipsoid is used, a = 6378137 m, f = 1/298.257223563.

     -w  toggle  the  longitude  first	flag (it starts off); if the flag is on,
	 then on input and output, longitude precedes latitude (except that,  on
	 input, this can be overridden by a hemisphere designator, N, S, E, W).

     -p prec
	 set  the  output  precision to prec (default 6).  prec is the number of
	 digits after the decimal point for lengths (in meters).  For latitudes,
	 longitudes, and azimuths (in degrees), the number of digits  after  the
	 decimal  point  is prec + 5.  For the scale, the number of digits after
	 the decimal point is prec + 6.

     --comment-delimiter commentdelim
	 set the comment delimiter to commentdelim (e.g., "#" or "//").  If set,
	 the input lines will be scanned for this delimiter and, if  found,  the
	 delimiter  and the rest of the line will be removed prior to processing
	 and subsequently appended to the output line (separated by a space).

     --version
	 print version and exit.

     -h  print usage and exit.

     --help
	 print full documentation and exit.

     --input-file infile
	 read input from the file infile instead of from standard input; a  file
	 name of "-" stands for standard input.

     --input-string instring
	 read  input  from  the  string instring instead of from standard input.
	 All occurrences of the line separator character  (default  is	a  semi-
	 colon) in instring are converted to newlines before the reading begins.

     --line-separator linesep
	 set  the  line  separator  character  to linesep.  By default this is a
	 semicolon.

     --output-file outfile
	 write output to the file outfile instead of to standard output; a  file
	 name of "-" stands for standard output.

EXAMPLES
	echo 48.648 -2.007 | GeodesicProj -c 48.836 2.337
	=> -319919 -11791 86.7 0.999
	echo -319919 -11791 | GeodesicProj -c 48.836 2.337 -r
	=> 48.648 -2.007 86.7 0.999

ERRORS
     An illegal line of input will print an error message to standard output be-
     ginning  with "ERROR:" and causes GeodesicProj to return an exit code of 1.
     However, an error does not cause GeodesicProj to terminate; following lines
     will be converted.

SEE ALSO
     The ellipsoidal gnomonic projection is derived in Section 8  of  C.  F.  F.
     Karney,  Algorithms  for  geodesics,  J.  Geodesy	87,  43-55  (2013);  DOI
     <https://doi.org/10.1007/s00190-012-0578-z>;  addenda:  <https://geographi-
     clib.sourceforge.io/geod-addenda.html>.

AUTHOR
     GeodesicProj was written by Charles Karney.

HISTORY
     GeodesicProj  was	added  to  GeographicLib, <https://geographiclib.source-
     forge.io>, in 2009-08.  Prior to version 1.9 it was called EquidistantTest.

GeographicLib 2.2		   2022-12-13			 GEODESICPROJ(1)

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