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All Topics | Topic "Snow Hydrology and PEST Calibration"
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Author Message
Miss Yiran Bai

Subject: Snow Hydrology and PEST Calibration   
Posted: 6/26/2018 Viewed: 8765 times
WEAP_Tutorial Page205.
when entering the expression
"If(PrevTSValue(Snow Depth[m])=0, Albedo Lower Bound,
PrevTSValue(Snow Depth[m],1)>PrevTSValue(Snow Depth[m],2),
Max(PrevTSValue(Albedo)-0.1, Key\Albedo\OldSnow))",
why is always appear "Expression refers to an invalid branch/variable combination"?
I have WEAP version 2017.
Mr. Jack Sieber

Subject: Re: Snow Hydrology and PEST Calibration   
Posted: 6/27/2018 Viewed: 8749 times
I am not sure why you are getting an error for that expression. I just tried it and had no problem.

I strongly encourage you to install the latest version of WEAP (2018.01). It has many new features and several bugs have been fixed. It might help your problem.

Ms. Kristen Bigland

Subject: Re: Snow Hydrology and PEST Calibration   
Posted: 8/31/2019 Viewed: 7302 times
Hi Yiran - I am having the same issue as you! I am using WEAP 2019.2.

I think I found the issue - page 205 of the tutorial says "Go to the Albedo data tab. Using the Expression Builder to make an expression. Enter the equation:.....". I read this as to a direction to select Albedo under Key Assumptions and boy, was that wrong. It is really referring to the Albedo data tab go the Climate section of the Snowy Mountain Demand Site. When you select Expression Builder on this tab, it's all good!

Hopefully this helps someone, because it had me stumped for at least an hour!

Topic "Snow Hydrology and PEST Calibration"