NAME¶
x_list - Extract Cross-Over Information from the Data Base.
SYNOPSIS¶
x_list [
leg1 ] [
leg2 ] [
-dataflags ] [
-R west/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"].
SEE ALSO¶
GMT(1),
x_system(1)
REFERENCES¶
Wessel, P. XOVER: A Cross-over Error Detector for Track Data,
Computers &
Geosciences, 15, 333-346.