x_list(1)
Extract Cross-Over Information from the Data Base.
SYNOPSIS
x_list [ leg1 ] [ leg2 ] [ -dataflags ]
[ -Rwest/east/south/north ]
[ -Xxbase ] [ -H ] [ -I ]
[ -V ] [ -Ccorrfile ] [ -Zignorefile ]
DESCRIPTION
x_list will allow the user to extract information from the xx_base.b and xx_legs.b files.
Several options can be passed on the command line in order to specify which parameters to
extract. They are:
- leg1 leg2
-
If two legs are specified, the cross-overs they have in common are returned. If one leg is
specified, all the external cross-overs involving this leg are returned, OR only its internal
cross-overs if -I is selected. If no legs are given, all the external (or internal with -I)
cross-overs are returned. This program is useful if one wants to look at, say, gravity COEs versus
time from port for a particular leg, etc.
- dataflags
-
This is a string of any combination of the following:
l means list both legnames.
t means list time.
x means list longitude.
y means list latitude.
g means list gravity COEs.
m means list magnetics COEs.
b means list bathymetry COEs.
G means list average gravity at cross-over.
M means list average magnetic anomaly at cross-over.
B means list average bathymetry at cross-over.
h means list heading of ship at cross-over.
The components are written out in the order they appear in dataflags. The default output is
-txygmbGMBhl. When internal COEs are desired, the time reported is the elapsed time since
the ship first occupied the cross-over point. For external COEs the time means time from the start
of the year in seconds.
- -R
-
Only return cross-overs inside the specified region west, east, south, and north. [Default is world].
- -X
-
Indicate alternate xx_base.b file.
- -H
-
Issue one header record on output.
- -I
-
Report on internal COEs [Default is external COEs].
- -C
-
Apply cross-over correction to the data (i.e. reports the cross-over value after the best-fitting
corrections have been applied to both legs). If no corrfile is given, the default correction file
is assumed.
- -Z
-
Ignore those legs that appear in the ignorefile.
- -V
-
Selects verbose mode, which will send progress reports to stderr [Default runs "silently"].
REFERENCES
Wessel, P. XOVER: A Cross-over Error Detector for Track Data,
Computers & Geosciences, 15, 333-346.