Wenn ich DEM-Rekonditionierung durchführe, enden einige Zellen als NoData.

Question

<\/HEAD>Ich habe zuerst die Gewässer nivelliert, ohne offensichtliche Probleme. Aber als ich anschließend die DEM-Rekonditionierung durchgeführt habe, enden einige Zellen als NoData. Warum? Das ist ein großes Problem. Gibt es eine Möglichkeit, den Quellcode für den Prozess zu erhalten, damit ich ihn überprüfen und bei Bedarf neu codieren kann? <\/P><\/BODY><\/HTML>

KirstenHazler · Answer

Glad to know it's not just me having the issue.  I have since abandoned the DEM Reconditioning tool and wrote my own algorithm in Python, which runs a modified AGREE procedure.  If anyone wants it, feel free to contact me.

BenjaminJackson · Answer

Hi,

I also encountered this problem and I too noticed that it only changed values of 0 to nodata. So I used a workaround that you might find useful: I ran raster calculator on my DEM and added 0.0000001 to all cells in the raster, this in effect removes 0s whilst effectively retaining them. Then I ran reconditioning on the result successfully.

In effect what I actually achieved was simply to convert the raster, since the precision required to add 0.0000001 is not available. I was using an Integer DEM and the resulting layer is Double precision 64bit. So I would suggest trying to convert the raster first and if that does not work, apply raster calculator with a very small number. Hopefully this will be fixed soon.

KirstenHazler · Answer

Update:  I have figured out that anywhere the input DEM is exactly 0, the reconditioning process returns NoData.  Clearly something is wrong with the algorithm.