topic Re: Use Arcade to Calculate Field Based on Options from Another Field in ArcGIS Pro Questions

Use Arcade to Calculate Field Based on Options from Another Field

ZachBodenner — Fri, 01 Sep 2023 16:15:05 GMT

Hello,

I've got an Arcade question. I have a feature set of points with an attribute "Type" that details the feature type. I have another attribute that is a numeric ID that corresponds to the text attribute Type. Example: Hydrant =1, Curb Stop = 2 etc. What's the best way to write an attribute rule in Arcade that will populate the numeric ID based on the value from the text type? My knee jerk is to do a super long If/Else exchange to the effect of:

var waterType = $feature.Type if (waterType='Hydrant'){ return 1; } if(waterType='Curb Stop'){ return 2; } etc

However, there are like, 60 possible types which strikes me as a bit onerous to put into an if statement like that. Is there a better way?

Re: Use Arcade to Calculate Field Based on Options from Another Field

KenBuja — Fri, 01 Sep 2023 16:39:53 GMT

Here are two possible ways of doing it. It is a little onerous to build it for your 60 types either way, but a little easier than using if statements.

Using a Dictionary

var dict = { 'Hydrant': 1, 'Curb Stop': 2 }; var waterType = $feature.Type return dict[waterType];

Using a When function

var waterType = $feature.Type; when (waterType == 'Hydrant', 1, waterType == 'Curb Stop', 2, -9999 //default value for any other type )

Re: Use Arcade to Calculate Field Based on Options from Another Field

ZachBodenner — Fri, 01 Sep 2023 17:00:05 GMT

Aha, yes without knowing it was thinking of a dictionary, which is a data type I'm pretty unfamiliar/uncomfortable with, so I want to try to use them more. However, I get an Arcade error that basically says the expression calculator couldn't find the attribute Type. Any thoughts on that?

Additionally, the second option, the When function, works perfectly!

Re: Use Arcade to Calculate Field Based on Options from Another Field

KenBuja — Fri, 01 Sep 2023 17:33:58 GMT

I wasn't running into any errors on the tests I ran. What did you code look like?

Re: Use Arcade to Calculate Field Based on Options from Another Field

ZachBodenner — Fri, 01 Sep 2023 18:01:03 GMT

I did an abbreviated dictionary/where as a test:

Not working

var dict = { 'Gate Valve': 87, 'Curb Stop': 12 }; var waterType = $feature.Feat_Code return dict[waterType];

Working:

var waterType = $feature.Feat_Code; when (waterType == 'Gate Valve', 87, waterType == 'Curb Stop', 12, -9999 //default value for any other type )

Re: Use Arcade to Calculate Field Based on Options from Another Field

KenBuja — Fri, 01 Sep 2023 19:19:21 GMT

Does Feat_Code have a Domain? If so, you'd have to use this code

var dict = { 'Gate Valve': 87, 'Curb Stop': 12 }; return dict[DomainName($feature, 'Feat_Code')];

Re: Use Arcade to Calculate Field Based on Options from Another Field

ZachBodenner — Fri, 01 Sep 2023 19:29:58 GMT

It does have a domain, and I had tried to use it, but I had entered it as part of the variable, like this:

var dict = { 'Gate Valve': 87, 'Curb Stop': 12 }; var waterType = DomainName($feature,Feat_Code) return dict[waterType];

That's clarifying, thank you!

Re: Use Arcade to Calculate Field Based on Options from Another Field

KenBuja — Fri, 01 Sep 2023 19:42:43 GMT

Your way would have worked, but you were missing the quotes around 'Feat_Code'