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EMS: how to initialize parameters for an equation with many variables

asked 2024-05-21 11:34:13 -0500

Leticia's avatar

updated 2024-05-21 15:35:20 -0500

I'm using EMS to set a logistic regression equation, but I'm having the following error message: "Error: EvaluateExpression: Variable = 'C50' used in expression has not been initialized!"

This error appears when I add variables to my equation. With only two variables (intercept plus one more) the simulation runs correctly. Ex: when my equation is: 'set handle=A35+B47Top' it runs ok when my equation is: 'set handle=A35+B47Top+C50*RH' I receive the above error message

My input objects for 'EnergyManagementSystem:Program' are: image description

For 'EnergyManagementSystem:ProgramCallingManager' they are: image description

Thank you for any help!

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Can you link to your IDF via e.g. Google Drive or Dropbox?

shorowit's avatar shorowit  ( 2024-05-22 07:00:40 -0500 )edit

Sure. The idf (version 9.6) and weather file are here: link text

Leticia's avatar Leticia  ( 2024-05-22 08:25:36 -0500 )edit

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answered 2024-05-22 17:16:01 -0500

Jamie Sullivan's avatar

Looking at your model, I believe the issue is that you don't have C50 in your global variables, so its value can't be passed between programs (the same with D61 etc.).

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Oh yes, the mistake was really simple, thank you! I think I went through it so much that I forgot a simple detail. Thanks a lot.

Leticia's avatar Leticia  ( 2024-05-26 08:11:29 -0500 )edit

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Asked: 2024-05-21 11:34:13 -0500

Seen: 99 times

Last updated: May 22