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RE: Pixel extraction
Pixel extraction
1/29/18 5:56 PM
Does anyone have example how to use `gpt PixEx` for one point not a region and only one band (do not want to extract all bands):

something like this:

gpt PixEx lat lon pathinput\*.nc pathout\dat.txt

Any idea will be appreciated.
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RE: Pixel extraction
1/31/18 8:53 AM as a reply to hans M savoni.
It is not possible in this way.

If you don't want to create a graph xml file, you need at least a coordinate file which contains your coordinate.
You can create such a file for example by exporting a pin.
See also the online help or the help on the console when you call gpt -h PixEx and gpt -h

Your command line call would look the following:
1gpt PixEx -PsourceProductPaths=pathinput\*.nc -PoutputDir=pathout/dir -PoutputFilePrefix=MyPrefix

But you can also create a graph XML file. Use the one which is printed when calling gpt -h PixEx as a template and configure PixEx in the GUI (Utilities / Extract Pixel Values). Save the parameters and put them in the template.
Then your call would look like:
1gpt pixExGraph.xml

best wishes
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RE: Pixel extraction
2/1/18 9:56 AM as a reply to Marco Peters.

I do not see where the coordinates file in your first command?

I noticed that the results (for all coordinates) are saved to only one .txt file. Is it possible to save the results (extraction) of each lat and lon to a .txt file. In other words to replace "prifix" with the name of the coordinates?
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RE: Pixel extraction
1/31/18 6:18 PM as a reply to hans M savoni.
Sorry, I forgot the coordinate file in the command line call. It should be:

1gpt PixEx -PcoordinatesFile=path/to/coordinates_file.txt -PsourceProductPaths=pathinput\*.nc -PoutputDir=pathout/dir -PoutputFilePrefix=MyPrefix

No, all extracted measurements are collected in one file. You need to rearrange the results to your needs.
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RE: Pixel extraction
2/1/18 6:13 PM as a reply to Marco Peters.
The best choic for me is
gpt pixExGraph.xml

but it is very slow. Is there a way to speed it up or to use multicores?

another question: it extracts all bands available in the file. I can not see where can I select one band (variables) to be extracted?
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RE: Pixel extraction
2/4/18 4:34 PM as a reply to hans M savoni.
No, there is no way to improve the speed.
Single bands can not be selected. You can only select to include bands, tie-point grids and masks.


But you can add another operator before the PixEx. The Subset operator. There you can define which bands you like to include.
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