Loop Attributes Not Working for Attribute Name Containing Space

Hi RM and Community - working in Studio 9.0.001 and trying to utilize Loop Attributes to convert several attributes from Nominal to Date.

I experienced the error "Error evaluating expression: the function 'eval' failed to parse the subexpression 'Bus Unit'. Cause: extraneous input Unit expecting operator."

My process utilizes Loop Attributes over a subset. Inside the loop there is a "Generate Attributes" operator attempting to generate "%{loop_attribute}_new" via an expression to convert the string to a Date. I have selected a single attribute "Bus Unit" to identify the issue but my use case is to select several.

I have found when I loop an Attribute with a space in the name - "Bus Unit" in this case - the exception is thrown. When I choose a single attribute of either poly/nominal or real type and the name does NOT contain a space, the loop attributes works wonderfully as expected.

I think this is a bug - can I get some feedback/assistance? I will attempt to utilize the "rename by replacing" operator to see if this helps. However I wouldn't expect spaces in the Attribute name to be a nuisance to RM.

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Accepted answers

Telcontar120

Spaces in attribute names are definitely a nuisance inside the expression editor. That's why in the current expression editor, attribute names with spaces are enclosed within square brackets. You could try doing the same thing with your macro, but probably the best solution is to strip out the whitespaces altogether with the Rename by Replacing operator.

All comments

Telcontar120

MartinLiebig

Hi,
i think you need to use
#{loop_attribute}_new
but i am confusing myself here all the time as well. @David_A is the local expression parser ninja.

BR,
Martin

jczogalla

Hi,

I think Martin is half right. You can keep the %{loop_attribute}_new to create the name of the new attribute, but you can use #{loop_attribute} inside the expression to reference the macro as an attribute. But I think, I'd like David to conform it.

Cheers

Jan

AustinT

Hey gents, just wanted to update. I don't know why I can't crack the code on the names of attributes which RM likes. Also, the "#{loop_attribute}" syntax isn't correct unless I'm missing something obvious.

This error is so frustrating! Why would "Stnd_Hrs_Wk" not be a valid attribute name to include in a Loop Attributes??!

Image: https://us.v-cdn.net/6030995/uploads/editor/wc/nd3ur31pmht1.png

AustinT

Oops - quick follow up: looks like my previous renaming efforts introduced a space next to the underscore so the actual attribute name is "Stnd_Hrs _Wk" so that's not a huge surprise. I'll go back with fiddling with the rename and loops.

Telcontar120

Glad you found that because underscores should be fine inside loops, macros, and Generate Attributes. I use them all the time. But definitely not spaces