Wanneer ik DEM-herconditionering uitvoer, eindigen sommige cellen als NoData.

Question

<\/HEAD>Ik heb eerst de waterlichamen geëgaliseerd, zonder schijnbaar probleem. Maar toen ik vervolgens DEM-herconditionering uitvoerde, eindigen sommige cellen als NoData. Waarom? Dit is een groot probleem. Is er een manier om de broncode van het proces te krijgen zodat ik het kan bekijken en indien nodig opnieuw kan coderen? <\/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.