1X_LIST(1)                    Generic Mapping Tools                   X_LIST(1)
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NAME

6       x_list - Extract Cross-Over Information from the Data Base.
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SYNOPSIS

9       x_list  [  leg1 ] [ leg2 ] [ -dataflags ] [ -Rwest/east/south/north ] [
10       -Xxbase ] [ -H ] [ -I ] [ -V ] [ -Ccorrfile ] [ -Zignorefile ]
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DESCRIPTION

13       x_list will allow the user to extract information  from  the  xx_base.b
14       and xx_legs.b files.  Several options can be passed on the command line
15       in order to specify which parameters to extract. They are:
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17       leg1 leg2
18              If two legs are specified, the cross-overs they have  in  common
19              are  returned.  If one leg is specified, all the external cross-
20              overs involving this leg are  returned,  OR  only  its  internal
21              cross-overs  if  -I  is selected.  If no legs are given, all the
22              external (or internal with -I) cross-overs are  returned.   This
23              program  is  useful  if  one wants to look at, say, gravity COEs
24              versus time from port for a particular leg, etc.
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26       dataflags
27              This is a string of any combination of the following:
28                   l means list both legnames.
29                   t means list time.
30                   x means list longitude.
31                   y means list latitude.
32                   g means list gravity COEs.
33                   m means list magnetics COEs.
34                   b means list bathymetry COEs.
35                   G means list average gravity at cross-over.
36                   M means list average magnetic anomaly at cross-over.
37                   B means list average bathymetry at cross-over.
38                   h means list heading of ship at cross-over.
39              The components are written out  in  the  order  they  appear  in
40              dataflags.  The  default  output is -txygmbGMBhl.  When internal
41              COEs are desired, the time reported is the  elapsed  time  since
42              the  ship first occupied the cross-over point. For external COEs
43              the time means time from the start of the year in seconds.
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45       -R     Only return cross-overs inside the specified region west,  east,
46              south, and north.  [Default is world].
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48       -X     Indicate alternate xx_base.b file.
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50       -H     Issue one header record on output.
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52       -I     Report on internal COEs [Default is external COEs].
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54       -C     Apply cross-over correction to the data (i.e. reports the cross-
55              over value after the best-fitting corrections have been  applied
56              to  both  legs). If no corrfile is given, the default correction
57              file is assumed.
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59       -Z     Ignore those legs that appear in the ignorefile.
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61       -V     Operate in verbose mode.
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SEE ALSO

64       GMT(1), x_system(1)
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REFERENCES

67       Wessel, P. XOVER: A Cross-over Error Detector for Track Data, Computers
68       & Geosciences, 15, 333-346.
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72GMT 4.3.1                         15 May 2008                        X_LIST(1)