Raster Calculator Output Empty

[AcyWood]

Hello,

I'm currently learning the very basics of ArcMap 10.2.2. I've bought a few textbooks in a series called An Introduction to GIS in Marine Biology and am working through a few simple exercises. Currently, I need to merge two raster layers, one made from point data and another made from polyline, into a single raster layer. I'm supposed to use the Map Algebra function, but unfortunately, I seem to be getting an empty output every time I try. My raster calculator function is extremely simple:

"bnd_raster_2" + "track_raster"

with the output being:

C:\GIS_EXERCISES\pa_raster

I am pretty confident that I created my raster layer correctly and have been told by a few sources that its possibly my Python that is the problem. I don't know how to address that issue currently. I've used Python 2.7.5 and 2.7.11 and both create empty file outputs. If anyone has any advice regarding how to check that my Python is alright of if somehow my raster calculator isn't set up properly, please let me know.

My next exercise depends on the pa_raster layer being created from merging the two raster layers. I was hoping someone could attempt to add the two together the rasters I've attached below on their own ArcMap or similar software to see if indeed I've made my rasters correctly. It would be very much appreciated.

Again, I'm very new to this. Please let me know if I'm using any terms wrong or am understanding any concepts wrong. I'm very excited to learn as much as I can and any input helps so much!

Thank you so much!

-AW

[NeilAyres]

Most of the issues around empty output revolve around coordinates systems (both must be the same) and whether the 2 rasters actually overlap. Have you looked at your inputs in ArcMap?

[AcyWood]

Thank you for your reply!

Both should be set to the same projections of a transverse_mercator and should have the same settings. The datum should be the same too, being the WGS 1984 one. I'm going to remake both layers from square one and see if it works just o be sure though!

[AbdullahAnter]

What about using Cell Statistics tool (  Cell Statistics ) .

Put two raster and choose Sum in Overlay statistic

[AcyWood]

I didn't know about that tool! I'll give it a try!

[AbdullahAnter]

why you use "merge" word in your question

My next exercise depends on the pa_raster layer being created from merging the two raster layers.

and you want to do sum for 2 raster

I'm supposed to use the Map Algebra function, but unfortunately, I seem to be getting an empty output every time I try. My raster calculator function is extremely simple:

"bnd_raster_2" + "track_raster"

if you want to merge raster , you can use Mosaic tool or Mosaic To New Raster.

Mosaic

Mosaic To New Raster

[AcyWood · Accepted solution]

I just uninstalled and reinstalled my ArcMap 10.2.2 to see if there was any corrupted data that I wasn't aware of. It turns out that Python was searching for a registry key that didn't exist due to a recent update. The statement 'PyWin_DLLVersionString' now reads "2.7-32" but the file location for the registry key was still "2.7" so adding the -32 to the registry key file location I was able to get the program to read the registry file allowing me complete usage of python again via ArcMap

Thank you everyone for your help!

[curtvprice]

This is a known issue that can come up when you use your own Python instead of going with the one that ArcGIS supplies. Unless you have a really good reason to do otherwise, I highly recommend people uninstall other Pythons before installing ArcGIS Desktop.