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CCT(1)				     PROJ				CCT(1)

       cct - Coordinate	Conversion and Transformation

	  cct [-cIostvz	[args]]	+opt[=arg] ... file ...

       cct  a 4D equivalent to the proj	projection program, performs transfor-
       mation coordinate systems on a set of input points. The coordinate sys-
       tem  transformation  can	include	translation between projected and geo-
       graphic coordinates as well as the application of datum shifts.

       The following control parameters	can appear in any order:

       -c <x,y,z,t>
	      Specify input columns for	(up to)	4 input	 parameters.  Defaults
	      to 1,2,3,4.

       -d <n>

       New in version 5.2.0: Specify the number	of decimals in the output.

       -I     Do the inverse transformation.

       -o <output file name>, --output=<output file name>
	      Specify the name of the output file.

       -t <time>, --time=<time>
	      Specify a	fixed observation time to be used for all input	data.

       -z <height>, --height=<height>
	      Specify  a  fixed	 observation  height  to be used for all input

       -s <n>, --skip-lines=<n>
	      New in version 5.1.0.

	      Skip the first n lines of	input. This applies to any kind	of in-
	      put, whether it comes from STDIN,	a file or interactive user in-

       -v, --verbose
	      Write non-essential,  but	 potentially  useful,  information  to
	      stderr.  Repeat for additional information (-vv, -vvv, etc.)

	      Print version number.

       The +opt	arguments are associated with coordinate operation parameters.
       Usage varies with operation.

       cct is an acronym meaning Coordinate Conversion and Transformation.

       The acronym refers to definitions given in the  OGC  08-015r2/ISO-19111
       standard	 "Geographical	Information  --	Spatial	Referencing by Coordi-
       nates", which defines two different classes of coordinate operations:

       Coordinate Conversions, which are coordinate operations where input and
       output datum are	identical (e.g.	conversion from	geographical to	carte-
       sian coordinates) and

       Coordinate Transformations, which are coordinate	operations where input
       and output datums differ	(e.g. change of	reference frame).

       1. The  operator	 specs	describe the action to be performed by cct. So
	  the following	script

	  echo 12 55 0 0 | cct +proj=utm +zone=32 +ellps=GRS80

       will transform the input	geographic coordinates into UTM	zone 32	 coor-
       dinates.	 Hence,	the command

	  echo 12 55 | cct -z0 -t0 +proj=utm +zone=32 +ellps=GRS80

       Should give results comparable to the classic proj command

	  echo 12 55 | proj +proj=utm +zone=32 +ellps=GRS80

       2. Convert geographical input to	UTM zone 32 on the GRS80 ellipsoid:

	  cct +proj=utm	+ellps=GRS80 +zone=32

       3. Roundtrip accuracy check for the case	above:

	  cct +proj=pipeline +proj=utm +ellps=GRS80 +zone=32 +step +step +inv

       4. As (2) but specify input columns for longitude, latitude, height and

	  cct -c 5,2,1,4 +proj=utm +ellps=GRS80	+zone=32

       5. As (2) but specify fixed height and time, hence needing only 2  cols
	  in input:

	  cct -t 0 -z 0	+proj=utm +ellps=GRS80 +zone=32

       6. Auxiliary data following the coordinate input	is forward to the out-
	  put stream:

	  $ echo 12 56 100 2018.0 auxiliary data | cct +proj=merc
	  1335833.8895	 7522963.2411	   100.0000	2018.0000 auxiliary data

       cct also	refers to Carl Christian Tscherning (1942--2014), professor of
       Geodesy	at the University of Copenhagen, mentor	and advisor for	a gen-
       eration of Danish geodesists, colleague and collaborator	for two	gener-
       ations  of  global  geodesists, Secretary General for the International
       Association of Geodesy, IAG (1995--2007), fellow	of the	American  Geo-
       physical	Union (1991), recipient	of the IAG Levallois Medal (2007), the
       European	Geosciences Union Vening Meinesz Medal (2008), and of numerous
       other honours.

       cct,  or	 Christian,  as	he was known to	most of	us, was	recognized for
       his good	mood, his sharp	wit, his tireless work,	and his	great  commit-
       ment  to	the development	of geodesy -- both through his scientific con-
       tributions, comprising more than	250 publications, and by his mentoring
       and teaching of the next	generations of geodesists.

       As  Christian  was an avid Fortran programmer, and a keen Unix connois-
       seur, he	would have enjoyed to know that	his initials would be used  to
       name a modest Unix style	transformation filter, hinting at the tireless
       aspect of his personality, which	was certainly one of  the  reasons  he
       accomplished so much, and meant so much to so many people.

       Hence, in honour	of cct (the geodesist) this is cct (the	program).

       proj(1),	cs2cs(1), geod(1), gie(1), projinfo(1)

       A      list	of	know	  bugs	   can	   be	  found	    at where new bug reports can be  sub-
       mitted to.


       Thomas Knudsen


6.3.1				 Feb 10, 2020				CCT(1)


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