topic Re: Unit converted parameter value not matching parsed string value in Revit API Forum

Unit converted parameter value not matching parsed string value

floretti — Wed, 10 Aug 2022 01:27:39 GMT

Hi all,

Thanks for your time first of all. Strictly speaking this is not a Revit API issue I'm facing but after some research I couldn't find the answer here or anywhere else but it's still a challenge related to Revit.

I'm comparing a family parameter value with values in a spreadsheet so I can update the parameter accordingly if they don't match but I'm getting weird results when comparing them. The snippet below shows how I'm extracting the double value of the WW_Width parameter and converting it to millimetres. Then I compare it to the a parsed string with the exact same value as a double but I get a false result to whether or not they match.

This is what my console shows as a result but I don't get why I'm getting a mismatch.

WW_Width UnitType: UT_Length StorageType: Double Value: 2448 Parsed string: 2448 Values match: False

Re: Unit converted parameter value not matching parsed string value

jeremy_tammik — Wed, 10 Aug 2022 06:04:31 GMT

You need to add some fuzz:

https://www.google.com/search?q=fuzz&as_sitesearch=thebuildingcoder.typepad.com

Re: Unit converted parameter value not matching parsed string value

floretti — Thu, 11 Aug 2022 07:31:37 GMT

@jeremy_tammik Thanks for the steer in the right direction. I wasn't aware of that issue with doubles/floats. Instead of directly comparing the doubles, I'm subtracting one from the other and checking if the difference is under a certain tolerance (e.g. A - B < 0.001) and that works.

This article explains it well in case anyone faces this issue in the future.

Re: Unit converted parameter value not matching parsed string value

jeremy_tammik — Thu, 11 Aug 2022 09:04:17 GMT

Brilliant! Glad that it helped, and thank you for the appreciation and nice helpful pointer.

Re: Unit converted parameter value not matching parsed string value

floretti — Thu, 11 Aug 2022 11:23:55 GMT

I'm always very thankful to these forums and the help I get here as I have no one around me to ask these questions to when I'm stuck.