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Changing window properties as a variable in OpenStudio Analysis Spreadsheet

asked 2017-01-24 04:26:08 -0600

Kingo gravatar image

updated 2017-08-05 13:08:36 -0600

I have been trying to find a way to change window properties such a U-value, SHGC and visable transmitance as a variable in the analysis spreadsheet so that i can observe the impact of different windows.

I havent been able to find a measure that can do this directly so i tried using "ReplaceExteriorWindowConstruction" instead and thought that maybe that could work, even though its a choice argument. So i renamed all me window constructions from 1-6 and added the discrete distribution from 1-6 (This is shown in the figure below):

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It did not work and i got the following error:

Failed with Could not set variable 'construction' of value 4 on model

If anyone knows how to work around this or where to find a better measure for the job i would be happy to hear from you :)

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double check your measure will accept numbers as constructions. my bet is that it will take the name of the construction. you can check the measure behavior in the OS GUI with 'apply measures now'.

BrianLBall gravatar imageBrianLBall ( 2017-01-24 09:49:08 -0600 )edit

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answered 2017-01-24 07:34:39 -0600

Adam Hilton gravatar image

updated 2017-01-24 10:35:14 -0600

NOT A CORRECT ANSWER. Keeping as answer to maintain integrity of comments below.

I could be wrong (fell free to slam that downvote button), but for choice values I believe you only want to fill out the 'default value' and 'enumerations' field. The other fields you filled out there don't apply (Min, Max, Mean, Standard Deviation, Discrete Values, Distribution).


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If it were me, I'd use a measure that just alters the U-Value, SHGC and VT of a particular construction. That way you can us a double type variable and continuously run through a range of possibilities.

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I think you're right, this was also a last resort kinda thing that i had a small hope would work. It would be much better to have a measure that just alters the values of a particular construction but the problem is i can't find such measure and im not skilled enough to write one myself :)

Kingo gravatar imageKingo ( 2017-01-24 07:57:17 -0600 )edit

That's an easy one! Try this one out. Just create a new measure in the OS interface and copy and replace the measure.rb in your new measure directory with the one I linked to and test it out.

Adam Hilton gravatar imageAdam Hilton ( 2017-01-24 08:56:54 -0600 )edit

unfortunately with the state of the analysis gem right now, you do actually need to fill out min/max/mean/stdv for all variables. I know it doesnt make sense, but we havnt had time to deal with all the cases specifically. The new PAT GUI will be smarter.

BrianLBall gravatar imageBrianLBall ( 2017-01-24 09:47:11 -0600 )edit

Hm, so for string choice arguments, what should you put there?

Adam Hilton gravatar imageAdam Hilton ( 2017-01-24 10:10:21 -0600 )edit

it doesnt matter, they dont get used in the OS-Sever, the fields are just checked that they exist on translation from the .xlsx to the analysis.json file which describes the workflow. I typically just put the default/static value in there.

BrianLBall gravatar imageBrianLBall ( 2017-01-24 10:29:03 -0600 )edit

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Asked: 2017-01-24 04:26:08 -0600

Seen: 109 times

Last updated: Jan 24