topic Re: Spatial Analyst Output Problem in ArcGIS Spatial Analyst Questions

Spatial Analyst Output Problem

SadiaNahar — Sat, 02 Jun 2018 03:23:16 GMT

Hello,

I am having problems using numerous spatial analyst tools. When I try to extract by attributes or reclassify a raster file, the output keeps coming out blank. There are no error pop-ups, just an empty output. I included pictures of how the window looks like. The output range of the extracted file is suppose to be between 2500 to 3550, instead the output range is 0.

Thanks

Re: Spatial Analyst Output Problem

XanderBakker — Sat, 02 Jun 2018 08:15:03 GMT

When I look at your second screenshot, I notice that the attribute table does reflect the correct values. The raster in the table of contents is showing the range 0 to 0 erroneously and probably need to have its statistics build explicitly. Try using: Build Pyramids And Statistics—Help | ArcGIS Desktop

Re: Spatial Analyst Output Problem

SadiaNahar — Sat, 02 Jun 2018 22:54:51 GMT

Hi Xander,

Thank you for replying. I am new to GIS, so I hope I can be clear. Based on the above picture, the values aren't correct because the values isn't within the 2500-3550 range. So I used Build Pyramids And Statistics in Data Management, I inputted the original denverdem raster file into the tool. Then I used the select by attributes, but this time the attribute table was completely empty.

I would appreciate it if you can give step by step direction.

Thank You!

Re: Spatial Analyst Output Problem

DanPatterson_Retired — Sat, 02 Jun 2018 23:08:19 GMT

If you want the elevations between that range, use the Con tool

Con( (Raster("elev") > 2500 ) & ( Raster("elev") < 4500), "elev", 0)‍‍

This portion

(Raster("elev") > 2500 ) & ( Raster("elev") < 4500)

will return a boolean, hence you need to use & instead of AND (if I remember correctly)

The rest of the Con statement basically says if the expression is True, then return the value in the "elev" grid otherwise, 0

Re: Spatial Analyst Output Problem

SadiaNahar — Sun, 03 Jun 2018 00:20:51 GMT

Hi Dan,

This is the con window.

Using & doesn't work, when I try to verify the query. Would I put the same raster for both the input conditional raster and input true raster?

Thank you for responding!

Re: Spatial Analyst Output Problem

DanPatterson_Retired — Sun, 03 Jun 2018 01:03:27 GMT

You don't put the expression I gave you in the Con tool.

put it in the Raster calculator... and you have to substitute my example grid name for your grid's name

Also... don't work in folders with spaces, especially if you are producing esri grids. (ie rasters without a file extension)

Re: Spatial Analyst Output Problem

Wei_Ying — Mon, 04 Jun 2018 23:30:39 GMT

Hi Sadia,

May I know what version of ArcMap are you using? I tried to repro using my own data in latest version of ArcMap, with the same expression as you did, but it works to me. Or maybe it is data specific.

I will appreciate if you can report your problem to our Technique Support with your detail repro steps, information and data (if possible). So that we can log it and investigate.

Thanks,

Wei

Re: Spatial Analyst Output Problem

Wei_Ying — Mon, 04 Jun 2018 23:33:22 GMT

And you also have such problem using Reclassify tool in this data? Can you also show how you did?

Re: Spatial Analyst Output Problem

NawajishNoman — Tue, 05 Jun 2018 01:30:01 GMT

Thanks!

What is Technique Support?

Sent from my iPhone

Re: Spatial Analyst Output Problem

DanPatterson_Retired — Tue, 05 Jun 2018 01:33:24 GMT

Technical Support https://support.esri.com/en/

Re: Spatial Analyst Output Problem

SadiaNahar — Tue, 05 Jun 2018 02:44:41 GMT

Wei,

I contacted my professor and she gave me a new EVA code. I have the ARCGIS 10.5.1 version. The entire spatial analyst tool wasn't working. But now with the new code the entire tool is working. If you want I can give you my old EVA code.

Re: Spatial Analyst Output Problem

DanPatterson_Retired — Tue, 05 Jun 2018 08:07:02 GMT

the eva code isn't shareable