## NAME

           gmtlist - A data-extractor for <legid>.gmt files

## SYNOPSIS

           gmtlist  leg-ids  [  -Ccorrectionfile ] [ -Dastartdate ] [
           -Dbstopdate  ]  [  -Fflags  ]  [   -G   ]   [   -H   ]   [
           -Rwest/east/south/north ] [ -Sastartdist ] [ -Sbstopdist ]
           [ -V ] [ -Wweight ] [ -b ]

## DESCRIPTION

           gmtlist reads <legid>.gmt files and produces an ASCII  [or
           binary] table. The <legid>.gmt files contain time(s), lat
           itude(y), longitude(x), gravity(g/G), magnetics(m/M),  and
           bathymetry(t/T),  and the user may extract any combination
           of these 6 parameters + distance(d), heading (h), velocity
           (v),  and  weight (w, see -W). A sub-section can be speci
           fied by passing time- or distance-intervals along track or
           by selecting a region.

           leg-ids
                  Can  be  one or more cruisenames. To give a list of
                  names, use `cat list_of_legs`.

## OPTIONS

           No space between the option flag and the associated  argu
           ments

           -C     Apply crossover Corrections to the data. If no cor
                  rection file is given, gmtlist  reads  the  default
                  correction  file.  (See  XSYSTEM  for how to set up
                  your own correction file)

           -Da    Do  not  list  data  collected   before   startdate
                  (mm/dd/yyyy/hh:mm) [Default is first day].

           -Db    Do   not   list   data   collected  after  stopdate
                  (mm/dd/yyyy/hh:mm). [Default is last day].

           -F     Can be any combination of syxgmtdhv to indicate the
                  desired  output  data.  The data will appear in the
                  order indicated by flags. If GMT is substituted for
                  gmt,  only  records  that  have that combination of
                  data are written out. If s is followed by c (calen
                  der), then yyyy/mm/dd/hh/mm/ss is written out, if s
                  is followed by j (julian), then yyyy/jd/hh/mm/ss is
                  written out. Default is seconds from start of year.

           -G     Force Geographical  longitudes  (-180/+180)  rather
                  than geodetic (0-360) [Default].

           -H     Issue  a  header  record  with  names for each data
                  field.

           -Sa    Do not list data that are less  than  startdist  km
                  along track from port of departure. [Default is 0].

           -Sb    Do not list data that are  more  than  stopdist  km
                  along  track  from  port  of departure. [Default is
                  length of track].

           -V     Selects verbose  mode,  which  will  send  progress
                  reports to stderr [Default runs "silently"].

           -W     Set the weight for these data. Weight output option
                  must be set in -F. This is useful if the  data  are
                  to  be  processed with the weighted averaging tech
                  niques  offered  by  blockmean,  blockmedian,   and
                  blockmode.

           -b     Selects  binary  output  mode (in double precision)
                  [Default  is  ASCII].  -H  is  ignored  if  -b   is
                  selected.   Julian  and calender dates are not sup
                  ported for binary time output (i.e., you  get  sec
                  onds from start of year).

## EXAMPLES

           To  get a (distance, heading, crossover-corrected gravity,
           bathymetry) listing from c2104.gmt,  starting  at  June  3
           1971  20:45 and ending at distance = 5000 km, use the fol
           lowing command:

           gmtlist c2104 -Da6/3/1971/20:45 -Sb5000 -Fdhgt -C > myfile

           To  make  input  for  blockmean  and surface using all the
           cruises listed in the file gmt.list,  but  only  the  data
           that  are  inside  the  specified  area,  and  make output
           binary, try:

           gmtlist `cat gmt.list` -Fxyg  -R-40/-30/25/35  -b  >  all
           grav.xyg

## SEE ALSO

           gmt(l), xsystem(l)

## REFERENCES

           Wessel,  P., and W. H. F. Smith, 2001, The Generic Mapping
           Tools (GMT) version 3.4 Technical  Reference  &  Cookbook,
           SOEST/NOAA.
           Wessel,  P.,  and W. H. F. Smith, 1998, New, Improved Ver
           sion of Generic Mapping Tools Released, EOS  Trans.,  AGU,
           79 (47), p. 579.
           Wessel,  P.,  and W. H. F. Smith, 1995, New Version of the
           Generic Mapping Tools Released, EOS Trans., AGU, 76  (33),
           p. 329.
           Wessel,  P.,  and W. H. F. Smith, 1995, New Version of the
           Generic Mapping Tools Released, http: American Geophysical
           Union.
           Wessel,  P., and W. H. F. Smith, 1991, Free Software Helps
           Map and Display Data, EOS Trans., AGU, 72 (41), p. 441.

                               15 Oct 2001                 GMTLIST(l)