topic Re: Calculating a field in Model Builder in Geoprocessing Questions

Calculating a field in Model Builder

JacobPederson1 — Mon, 08 Jul 2013 23:16:42 GMT

Hi,

I am a non-programming user who is learning model builder for the first time. I've had success creating my initial workflow, but am having trouble calculating a field, based off of other fields already present in my polygon layer. The calculation is simple, multiplying one field by 2, and dividing the product by another. When I verify and run, I get the "Item not found in this collection" error. I have attached the .py file, and appreciate any advice! Thanks!

Re: Calculating a field in Model Builder

DuncanHornby — Thu, 11 Jul 2013 12:43:42 GMT

Your calculate expression is invalid, you have:

"[Shape_Length * 2] / [Join_Count]"

it should be:

"[Shape_Length] * 2 / [Join_Count]"

Duncan

Re: Calculating a field in Model Builder

JacobPederson1 — Thu, 11 Jul 2013 15:19:13 GMT

Thanks Duncan, problem is all cleared up. Just made my first functioning model!
-Hacib

Re: Calculating a field in Model Builder

DuncanHornby — Thu, 11 Jul 2013 15:46:44 GMT

Jacob,

Glad to have helped, but you should mark your post as answered. Also if you see a good question/answer vote it up! People love you for it.

Duncan

Re: Calculating a field in Model Builder

JacobPederson1 — Thu, 11 Jul 2013 16:05:37 GMT

Perhaps I'm going blind....where is the tool to mark a thread as answered?

Re: Calculating a field in Model Builder

LangdonSanders3 — Fri, 12 Jul 2013 12:17:53 GMT

Perhaps I'm going blind....where is the tool to mark a thread as answered?

If you are the thread author you can click a check mark on the left of the reply - it is grey'd out and will turn green.

Re: Calculating a field in Model Builder

Anonymous User — Fri, 12 Jul 2013 13:37:05 GMT

To see how to reward Duncan for his answer, see this page describing the MVP" rel="nofollow" target="_blank">http://resources.arcgis.com/en/help/forums-mvp/]MVP Program.