NAME

       rotconverter - Manipulate total reconstruction and stage rotations

SYNOPSIS

       rotconverter  [  +|-  ] rotA [ +|- rotB ] [ +|- rotC ] ... [  -A ] [  -D ] [  -E[fact] ] [
       -Fout ] [  -G ] [  -N ] [  -S ] [  -T ] [  -W ] [  -V[level] ] [ -hheaders ]

       Note: No space is allowed between the option flag and the associated arguments.

DESCRIPTION

       rotconverter reads one  or  more  plate  motion  models  (stage  or  total  reconstruction
       rotations) stored in the given files. If more than one plate motion model is given we will
       add or subtract them in the order they were listed. The minus sign means we  should  first
       transpose  the  rotation  and  then  add  it to the previous rotation. If a file cannot be
       opened we will attempt to decode the file name as a single rotation whose  parameters  are
       separated by slashes.

REQUIRED ARGUMENTS

       rotX   Name  of  a  file  with  a  plate motion model. Separate several files with desired
              operator (+ or -). The very first file may also have a leading  minus  operator  to
              imply  a transpose. We also recognize filenames of the form A-B, where both A and B
              are uppercase plate abbreviations as used by GPlates, to indicate we should look up
              the  rotation  between the two plates in the GPlates rotation file (e.g., PAC-MBL).
              If any of the specified rotation models cannot be opened as a file, we will try  to
              decode the file name as lon/lat/tstart[/tstop]/angle for a single rotation given on
              the command line. The tstop argument is required for stage poles only. For a single
              total  reconstruction  rotation  without  any  time information, give lon/lat/angle
              only.

OPTIONAL ARGUMENTS

       -A     Indicate that times are actually just opening angles [times in Myr].

       -D     Report longitudes use the -180/+180 range [Default is 0/360].

       -E[fact]
              Scale opening angles by fact on output [0.5].  Typically  used  to  get  half-rates
              needed for flowlines.  Requires stage pole output (see -F).

       -Fout  Specify  the  output  format  for rotations. The out flag must be either t or s for
              total reconstruction or stage rotations,  respectively.  [Default  is  -Ft  (output
              contains total reconstruction rotations)].

       -G     Output  final  rotations  in the Plates4 format used by GPlates [Default is spotter
              format].

       -N     Place all output  poles  in  the  northern  hemisphere  [Default  reports  positive
              rotation angles].

       -S     Place  all  output  poles  in  the  southern  hemisphere  [Default reports positive
              rotation angles].

       -T     Transpose the final result, i.e., change the sign of the rotation angles.

       -W     Ensure all output rotations have negative opening angles [Default reports  positive
              rotation angles].

       -V[level] (more ...)
              Select verbosity level [c]. Report statistics of extracted rotations.

       -^ or just -
              Print a short message about the syntax of the command, then exits (NOTE: on Windows
              just use -).

       -+ or just +
              Print  an  extensive  usage  (help)  message,  including  the  explanation  of  any
              module-specific option (but not the GMT common options), then exits.

       -? or no arguments
              Print  a  complete  usage (help) message, including the explanation of all options,
              then exits.

LIMITATIONS

       Note that only one of  -N,  -S, and  -W can be used at the same time.

EXAMPLES

       To convert the total reconstruction rotations in the  file  model_total_reconstruction.APM
       to stage poles, run

              gmt rotconverter model_total_reconstruction.APM -Fs > model_stages.APM

       To obtain Nazca motion relative to Pacific hotspots by adding the motion of Nazca relative
       to a fixed Pacific to the Pacific-Hotspot reference model DC85_stages.d,  and  report  the
       result as total reconstruction reconstruction poles in the northern hemisphere, try

              gmt rotconverter DC85_stages.APM + Pac_Naz_stages.RPM -N -Ft > \
                               Naz_HS_total reconstruction.APM

       To add the final rotations ROT(150.1, 70.5, -20.3) and ROT (145.0, 40.0, 11.4), try

              gmt rotconverter 150.1/70.5/-20.3 + 145/40/11.4

       which prints out 157.32, -80.44, 11.97.

       To make stage rotations suitable for generating flowlines (fracture zones) from a model of
       relative plate motions PL1-PL2.RPM, assuming symmetric spreading, try

              gmt rotconverter PL1-PL2.RPM -E -Fs > PL1-PL2_half.RPM
              gmt rotconverter - PL1-PL2.RPM -E -Fs > PL2-PL1_half.RPM

       To compute rotations for India  relative  to  a  fixed  Africa  using  the  plate  circuit
       India-Central Indian Basin-Antarctica-Africa, based on the GPlates rotations database, try

              gmt rotconverter IND-CIB CIB-ANT ANT-AFR > India_Africa.RPM

NOTES

       GMT  distributes the EarthByte rotation model Global_EarthByte_230-0Ma_GK07_AREPS.rot.  To
       use an alternate rotation file, create an environmental parameters named GPLATES_ROTATIONS
       that points to an alternate rotation file.

SEE ALSO

       backtracker,  grdrotater,  grdspotter,  gmtpmodeler,  grdpmodeler, grdrotater, hotspotter,
       originator

COPYRIGHT

       2019, P. Wessel, W. H. F. Smith, R. Scharroo, J. Luis, and F. Wobbe