Refining Data

Radial Post-Processing (filtering)

With this tool, you can:
1. Filter out all velocities greater than some threshold.
2. Filter out all velocities greater than some threshold whose vectors are within sector area.
3. Filter out all vectors within a sector area.

The filtered vectors can be removed, flagged, or unflagged from the output. Flagged angseg values have a +128 vector flag. SeaDisplay 6.2.3 will not show these normally. Flagged maxvel values have a +32 flag. Currently SeaDisplay still shows these.

Using flags are good because the original information is still in the file; just not shown or used in Combining.

The sector area can be an angseg.txt file or one that you build through the command line. With a sector area you can filter out early ranges with "-zero=No" or "-zero" which indicates whether the area should start from zero distance or the first distance specified. You can also filter out farthest range cells with "-closed=Yes" or "-closed" which indicates that the last sector doesn't go out forever.

An angular sector is typically assumed to be at the same origin as the radial. This assumption is very limited. An angseg specifies an area that vectors should be with in. Using the radial site's origin, the angseg can be used with other sites within the area.

You can build your own area by specifying params "-range=<km>" followed by one or more "-sector=a1,a2" for the range where the sector is a1 CW to a2 and a1,a2 are degrees True. You can multiple "-range" and "-sector"keys. Ranges must be in increasing distance. (Hint: use "-range=0 -sectior=a2,a1" where a2,a1 are the coastline angles in the Header.txt which go CCW hence use a2,a1 to get coastline cutoff).

Use "-h" or "-help" for help info

./lluvcutoff -h
-diag=<verbocity> --Output diagnostics to stdout.
<verbocity> 0=quiet,1000=all.
-version --Output version.
-source=<folder/file> --Set source folder or file to start with.
-startwith=<string> --Use only sources that start with <string>.
-angseg=<file> --Angular area file to use.
-origin=<lat>,<lon> --New Origin of Angular area.
-output=<folder/file> --Where to put the filtered radial.
If folder use standard naming with lluvtype,lluvsuffix. (Default <source>)
-method=<type> --Filter method: remove/flag/unflag (Default flag)
-lluvtype=<char> --LLUV output char type. (4th char of filename) (Default use source type).
-lluvsuffix=<suffix> --LLUV output filename suffix before extension (Default "")
-invert --Invert the angseg or sector area.
-range=<dist km> --Angular sector range. Follow with one or more -sector. Optionally add more ranges.
-sector=<a1,a2> --Angular sector a1 CW to a2 True
-closed=<yes/no> --Cutoff all vectors beyond last angseg range (Default no)
-zero=<yes/no> --Don't cutoff vectors before first angseg range (Default yes)
-maxvel=<cm/s> --remove/flag vectors beyond this velocity.

If the source is a folder then it will walkthrough all files filtering those with "-startwith=".

The "-output" can specify an output file or a folder to put the results. If an output folder, the source name will be used with optional "-lluvtype" and "-lluvsuffix" settings.



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