topic Re: ArcGIS Pro 3.0.4 - Python Script Failing for Labels in ArcGIS Pro Questions

ArcGIS Pro 3.0.4 - Python Script Failing for Labels

AnthonyBomba — Wed, 15 Mar 2023 15:38:16 GMT

I recently upgraded from 2.7 to 3.0.4. This code worked perfectly in 2.7 but seems to have stopped working after I upgraded. I've seen similar posts to this but I don't know if the issue was ever resolved.

def FindLabel ( [SURFACTANTS], [AMMONIA], [CHLORINE] ): surf, amm, chlor = "","","" if float([SURFACTANTS]) >0.24: surf = "Surfactants: " + [SURFACTANTS] + "\n" if float([AMMONIA]) >= 0.5: amm = "Ammonia: " + [AMMONIA] + "\n" if float([CHLORINE]) >= 0.02: chlor = "Chlorine: " + [CHLORINE] return surf + amm + chlor

The error message I'm getting is:

Invalid expression.
Error on line 1.
Semicolon or new line expected

I'm not sure where a semicolon or new line is expected, but I'm hoping it's an easy fix

Re: ArcGIS Pro 3.0.4 - Python Script Failing for Labels

DanPatterson — Wed, 15 Mar 2023 15:47:15 GMT

If you are using a python parser and these

[SURFACTANTS], [AMMONIA], [CHLORINE]

are supposed to be field names, you need to replace [] with surrounding ! !

Re: ArcGIS Pro 3.0.4 - Python Script Failing for Labels

AnthonyBomba — Wed, 15 Mar 2023 16:02:27 GMT

I am using a python parser and I just included surrounding ! ! but I still seem to be getting the same error message. One additional thing to note is that in previous versions the "def" in def FindLabel was highlighted blue (assuming it's a function), but that doesn't happen in the current version. Could the issue in line 1 be there?

Re: ArcGIS Pro 3.0.4 - Python Script Failing for Labels

RhettZufelt — Wed, 15 Mar 2023 17:11:39 GMT

along with the fields as @DanPatterson mentioned, it appears as if it has lost it's indentation (at least in the pasted example).

Need to indent everything below line one.

Re: ArcGIS Pro 3.0.4 - Python Script Failing for Labels

AnthonyBomba — Wed, 15 Mar 2023 17:30:57 GMT

Thank you for the help @RhettZufelt and @DanPatterson . Here is what the code looks like now

def FindLabel ( !SURFACTANTS!, !AMMONIA!, !CHLORINE! ): surf, amm, chlor = "","","" if float(!SURFACTANTS!) >0.24: surf = "Surfactants: " + !SURFACTANTS! + "\n" if float(!AMMONIA!) >= 0.5: amm = "Ammonia: " + !AMMONIA! + "\n" if float(!CHLORINE!) >= 0.02: chlor = "Chlorine: " + !CHLORINE! return surf + amm + chlor

I still seem to be getting the same error message though.

Re: ArcGIS Pro 3.0.4 - Python Script Failing for Labels

RhettZufelt — Wed, 15 Mar 2023 17:51:06 GMT

Well, it appears as if Pro labeling likes the [] instead of !! for the field names, However, the only way I get the same error message is if I fail to switch the language to Python "before" I paste in the code.

Re: ArcGIS Pro 3.0.4 - Python Script Failing for Labels

SLouq — Wed, 15 Mar 2023 17:56:51 GMT

I'm no Python expert but I have used expressions for labeling and I have used the FindLabel function like you shared in your graphic. To my knowledge, that isn't the syntax for python. That is the syntax for VBScript.

Re: ArcGIS Pro 3.0.4 - Python Script Failing for Labels

RhettZufelt — Wed, 15 Mar 2023 18:14:28 GMT

I thought that the variables were being called with VBScript syntax, but according to the documenation, and the fact that clicking/building it in Pro's label editor populates it this way, I tried it and it works. It appears as if the python syntax/variable delineators are different in label expressions vs calculate epxressions (where fields are referenced with !field!).

Re: ArcGIS Pro 3.0.4 - Python Script Failing for Labels

AnthonyBomba — Wed, 15 Mar 2023 18:16:31 GMT

This fixed it! I'm glad it was something small like that and not a syntax error. Appreciate the help!

Re: ArcGIS Pro 3.0.4 - Python Script Failing for Labels

SLouq — Wed, 15 Mar 2023 18:25:24 GMT

glad it worked!