Search found 8 matches

by bytenc
Wed Jul 15, 2009 2:03 pm
Forum: Vensim
Topic: Optimising using constraint
Replies: 24
Views: 19520

For those who are following: To make a variable 0<="Percentage"<=1 vary with a 1% increment in a optimization processes you should set: Multiple Start = Vector Vector Points = 101. If you have "Percentage" with subscript it will vary each one with a 1% increment. The only thing I...
by bytenc
Tue Jul 14, 2009 2:51 pm
Forum: Vensim
Topic: Optimising using constraint
Replies: 24
Views: 19520

Another question:

When doing the optimization the percentage is varying with too many digits. I would like to vary them just with an 1% increment. This would save a lot of time. How can I do that?

Tks

Felipe
by bytenc
Mon Jul 13, 2009 4:19 pm
Forum: Vensim
Topic: Optimising using constraint
Replies: 24
Views: 19520

JJ,
Now I managed to make it work. I just changed Multiple Start to Random. In the file it was set to Off.
It's great! Tks a lot!
by bytenc
Mon Jul 13, 2009 1:46 pm
Forum: Vensim
Topic: Optimising using constraint
Replies: 24
Views: 19520

JJ,
This very general method is not working. After optimization it's giving as result var1=2, var2=1 and not the correct one var1=10, var2=9.
Felipe
by bytenc
Fri Jul 10, 2009 4:26 pm
Forum: Vensim
Topic: Optimising using constraint
Replies: 24
Views: 19520

BOB and TONY, I finally got what you said and now it's working fine. I didn't even had to fix a value for one State. I just run it varying from 0 to 1 for all of them and the result is good! Tks TONY, I just got the book by mail. Tks again guys! LAUJJL, I opened your files and it's exactly the same ...
by bytenc
Thu Jul 09, 2009 9:50 pm
Forum: Vensim
Topic: Optimising using constraint
Replies: 24
Views: 19520

Tony, Bob and LAUJJL Tks for the help. Using Tony idea it would not work since the system would give me as best result all the State having 100%, which would then give me the "proportional percentage" = 1/9 for every single one. Using Bob idea, it would be me as you said at least one State...
by bytenc
Wed Jul 08, 2009 3:11 pm
Forum: Vensim
Topic: Optimising using constraint
Replies: 24
Views: 19520

Noap. There are 9 States. This approach will not work. Any new ideas?
by bytenc
Wed Jul 08, 2009 2:50 pm
Forum: Vensim
Topic: Optimising using constraint
Replies: 24
Views: 19520

Optimising using constraint

Simple problem: to optimise a model using a constant "Percentage" which has a subscript "State". State can be or "A" or "B" and the Percentage[State] can vary from 0 to 1. This is easy. Now the constraint: Percentage[A]+Percentage must be equals to 1. I tried ...