Search found 14 matches

by pelorn
11 months ago
Forum: Solvers
Topic: Initial Function Value too Large
Replies: 1
Views: 535

Initial Function Value too Large

Hi there, I get the following error message if I increase a parameter above a certain threshold: ** An initial function value is too large (larger than 1.0E+10). Scale the variables and/or equations or add bounds. Is there a way I can get GAMS to tell me which value gets too large? I can't figure ou...
by pelorn
11 months ago
Forum: Modeling
Topic: Multiple Conditions in one Equation
Replies: 4
Views: 770

Re: Multiple Conditions in one Equation

Hey,

It didnĀ“t work the way I tried it with the multiple =E= signs.

And I don't know the value, I try to optimize different paths that diverge, but they need to be equal in the first period.

Thanks
by pelorn
11 months ago
Forum: Modeling
Topic: Multiple Conditions in one Equation
Replies: 4
Views: 770

Multiple Conditions in one Equation

Hi there,

I want to set multiple variables equal to each other without having to define multiple equations for that. Is there a smooth way to do this?

I.e. something like this:

Neweq.. AI("1")=E=BI("1")=E=CI("1")=E=DI("1")

Thank you
by pelorn
11 months ago
Forum: Modeling
Topic: Double Exponent in Objective Function
Replies: 5
Views: 621

Re: Double Exponent in Objective Function

Hi Michael, Basically, I try to replicate a paper by Ackerman et al. (2013) who introduce Epstein-Zin preferences into the model. For that, I would run the model simultaneously for six different states of climate sensitivity (the code below is only for two states) from period 10 onwards, collapse th...
by pelorn
11 months ago
Forum: Modeling
Topic: Double Exponent in Objective Function
Replies: 5
Views: 621

Re: Double Exponent in Objective Function

Hey, Thanks for your replies. So real and floating numbers are not precisely the same, but how can that have such a big effect on the model? If I try to run the model with an exponent of say 1.000001 in the objective function, leaving everything unchanged (I am trying to modify one thing in the DICE...
by pelorn
1 year ago
Forum: Modeling
Topic: Sum function from t=2
Replies: 2
Views: 426

Re: Sum function from t=2

Thanks again Fred!
by pelorn
1 year ago
Forum: Modeling
Topic: Sum function from t=2
Replies: 2
Views: 426

Sum function from t=2

Hi there,

How can I use the sum function only from the second or later period (t=2) instead of all t? sum(t, periodutility(t))

Cheers
by pelorn
1 year ago
Forum: Modeling
Topic: Change Equation over time
Replies: 4
Views: 592

Re: Change Equation over time

Cool, thank you!
by pelorn
1 year ago
Forum: Modeling
Topic: Double Exponent in Objective Function
Replies: 5
Views: 621

Double Exponent in Objective Function

hi there, I want to include a function in the objective function that requires the objective to be squared first, multiplied with its probability, and then squared with the inverse again. I tried the following function to figure it out: (power((sum(t, CEMUTOTPER(t))),2))**0.5 How can I make sure tha...
by pelorn
1 year ago
Forum: Solvers
Topic: Exponent in Objective Function
Replies: 0
Views: 542

Exponent in Objective Function

Hi there,

In my model, if I leave everything the same but I include an exponent in the objective function, I get the rPower: FUNC DOMAIN: x**y, x < 0 error message.

What is the reason for that? If I run the model without that exponent modification, x is a positive number.

Many thanks