topic Re: Iterator not working in ArcGIS Spatial Analyst Questions

Iterator not working

Anonymous User — Wed, 20 May 2020 15:23:31 GMT

Hello,

I am currently attempting a Least Cost Path analysis, specifically, a "From everywhere to everywhere model".

Cost raster = Slope_Raster

Surface raster = 0 value extracted_DEM

Vertical Factor: Tobler Away

To achieve thus multi-path approach, I made my destination (which, according to this model, will also become origins) points through the Fishnet tool, settling for a 25kmx25km grid. I then put this fishnet through "Split by attributes" to acquire individual points that I could run separately through the Path distance tool. I then merged these points so that I could run them collectively through "Iterate Feature Selection" in Model Builder.

It is at this stage that I encounter a problem. When the Model runs, it only iterates through the first three points of the merged points. I have tried selecting different fields, and I have even tried to achieve an iteration through a separate tool ("Iterate feature class"). No matter what variation I try, the same issues arises; the model only create paths for the first three points out of the entire 83 point feature.

I am at a loss as to what to do, and cannot seem to find what is causing this error.

Thank you in advance.

P.S. I know this method of achieving multiple pathways is possible as I used the same model building technique in ArcMap 10.7.1 and it worked (However the processing was incredibly slow).

Re: Iterator not working

curtvprice — Sun, 31 May 2020 14:43:15 GMT

Unclear to me why it would stop after three iterations.

One thing I noticed though, I suggest you put the iterator inside a submodel so you don't run the path distance over and over again on every iteration. Iterators re-run all tools in the model (unless you somehow prevent this with a precondition logic - a sub model is an easier way to control that).

If you must run it every iteration (unclear), you may want to set a precondition from the output to the iterator to the path distance tool, to make sure the path distance runs after the selection is made.

Re: Iterator not working

JacobCurrie — Mon, 23 Oct 2023 16:29:53 GMT

I realize this is an old issue. I encountered the same problem.

Windows 11, ArcGIS Pro 3.1.2, Model Builder

Problem:

I would run a model in ModelBuilder using an Iterator that processed 5 times. Sometimes it would iterate 3 times and others it would stop part way through the 5th and final iteration.

Findings:

I noticed that my system temp files volume was massive. I also saw that my .gdb size was huge. The volumes seem to grow a lot as I worked with, adjusted, and re-ran the model.

My Solution:

-Clear the system temp files

-Compact my project .gdb

-Set the project layer cache to be deleted at the end of the session

Result:

Worked without issue afterwards.