I think your issue is more with the AttributeRenamer than with the Python scripted parameter here. In your place I would have dropped the scripted parameter and the AttributeRenamer altogether, replacing it with a PythonCaller with the following code:

 

 

import fmeobjects   def DynamicAttributeRenamer(feature):     tc1 = FME_MacroValuesa'Test_Condition_1']     old_name, new_name = tc1.split('_')     feature.setAttribute(new_name, feature.getAttribute(old_name))     feature.removeAttribute(old_name)

 

 

This will read a published parameter "Test_Condition_1" and, assuming a value of "ONE_AAA", will rename the attribute "ONE" to "AAA".

 

 

Hope this helps.

 

 

David

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David,

 

 

I thought about PythonCaller, but again documentation was very inadequate, so I wasn't sure where to begin with it.  This might be the right way to go, but I still have some questions.

 

 

First of all, I think you misunderstood what I was trying to do.  The field is named "ONE_AAA" in the table and I want to rename it to "AAA" (I'm not going from "ONE" to "AAA").  Because some fields can have more underscores after the initial prefix, I chose not to use the split() function.

 

 

Anyway, questions what do I put in as the entry point?  Would that be just "DynamicAttributeRenamer", right?  And am I exposing any attributes?

 

 

Thanks,

 

John

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David,

 

 

I just got your script to run and it doesn't do what I want.  It's erasing my existing data and replacing it with "ONE" throughout the table.  Maybe I worded what I was trying to do incorrectly.  I do not want to change the data in the tables at all.  I just want to change the field names from "ONE_AAA" to "AAA" and copy the data over from a different bit of logic I have that works fine.

 

 

Sorry for the confusion,

 

John

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Ok, after a big of messing around with the data, I got it to work.  I had null values which was causing the script to crash my workspace and I had to handle it.  This works great.  Thanks David.

 

 

Though, I am still would love for someone to explain scripted parameters to me.

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Hi Johnny,

 

 

good to hear that you got it to work.

 

 

Scripted parameters are (published or private) parameters with a value that is calculated by a script rather than given as-is on the command line. They really aren't much more complicated than that.

 

 

Here is an example use case for a scripted parameter:

 

http://fmepedia.safe.com/articles/How_To/Pass-a-List-of-Tables-or-Layers-to-an-FME-Reader-using-Python-Scripted-Parameters

 

 

Examples of other use cases:

• reading settings from a configuration file
• retrieving an authentication token from a webservice
• calculating the output file name base on the input parameters
• etc...

 

Hope this helps.

 

 

David

 

 

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