topic Re: How to extract a bigger raster with a smaller raster in the way that the bigger raster has NoData where the smaller raster cells are? in ArcGIS Spatial Analyst Questions

How to extract a bigger raster with a smaller raster in the way that the bigger raster has NoData where the smaller raster cells are?

JuttaSchiller — Wed, 28 Sep 2016 14:15:48 GMT

How to extract a bigger raster with a smaller raster in the way that the bigger raster has NoData where the smaller raster cells are?

I want to extract the raster cells from a big raster with the raster cells from a smaller raster which is overlapping with the bigger raster. Unfortunately, I cannot find a tool for that in ArcMap 10.3.1, but is there a way to do it? I do not want to subtract the values, but there should be noData in the new bigger raster where the bigger raster is overlapping with the smaller raster, like a hole in the bigger raster with the extent of the smaller one.

I tried this:

Con(IsNull("smaller"),"bigger","bigger" == "smaller")

But I really need to put the values from the smaller raster extension into noData in the new raster.

Thank you.

Re: How to extract a bigger raster with a smaller raster in the way that the bigger raster has NoData where the smaller raster cells are?

DanPatterson_Retired — Wed, 28 Sep 2016 14:30:26 GMT

setnull and setnull the tool

Re: How to extract a bigger raster with a smaller raster in the way that the bigger raster has NoData where the smaller raster cells are?

NeilAyres — Wed, 28 Sep 2016 15:05:00 GMT

You were very close, try :

Con(IsNull("smaller"),"bigger", "smaller")

Re: How to extract a bigger raster with a smaller raster in the way that the bigger raster has NoData where the smaller raster cells are?

NeilAyres — Wed, 28 Sep 2016 15:06:13 GMT

Or if you actually want the hole...

Con(IsNull("smaller"),"bigger", SetNull("smaller"))

Re: How to extract a bigger raster with a smaller raster in the way that the bigger raster has NoData where the smaller raster cells are?

JuttaSchiller — Thu, 29 Sep 2016 08:59:27 GMT

Cool, thank you! This is working: Con(IsNull("smaller"),"bigger", "smaller"), using 9999 as value for the smaller raster, than the tool ‘int’ and the tool ‘extract by attributes’. But there is another big problem now: The extension of the bigger raster is the same than the extension of the smaller raster. How can I fix this?

Thanks for responding

Re: How to extract a bigger raster with a smaller raster in the way that the bigger raster has NoData where the smaller raster cells are?

JuttaSchiller — Thu, 29 Sep 2016 09:12:23 GMT

Okay, I fixed the problem by using the ModelBuilder and set the bigger raster as environments for extent, snap and mask.