Search found 13 matches

by m_tanawat
5 months ago
Forum: Syntax
Topic: GAMS sum and prod syntax_ what different?
Replies: 2
Views: 240

Re: GAMS sum and prod syntax_ what different?

Hi Fred,

Many thanks for your reply.
I totally understand it now.

Best regards,
by m_tanawat
5 months ago
Forum: Syntax
Topic: GAMS sum and prod syntax_ what different?
Replies: 2
Views: 240

GAMS sum and prod syntax_ what different?

Hi all, I read GAMS manual and find some unclear points. I want to know what is the prod meaning in GAMS? I know that it uses same sysntax as sum. But I am not sure what is it implying in economics. Sum(j, x(j)) = x1+x2+x3+....xn What prod(j, x(i, j)) is equivalent to? Note that I see it uses with o...
by m_tanawat
6 months ago
Forum: Modeling
Topic: uncontrolled set entered as constant
Replies: 1
Views: 247

uncontrolled set entered as constant

Hi there, I want to represent my production equation X=AX*d in GAMS. However, when I fill in the equation,it showed uncontrolled set entered as constant error. I supposed that error come from set since I plus the different set together. But I am not sure if I want to write this GAMS equation syntax ...
by m_tanawat
6 months ago
Forum: Syntax
Topic: Syntax equation
Replies: 0
Views: 132

Syntax equation

Hi there,

I am practicing building IO model by using GAMS.
I try to formulate equation syntax to represent IO, but I cannot do it.
So I cannot let program to calculate x1,x2,x3,m,w,depr and profit per sector.

I attached my GAMS file. Could you please advise?
Thank you so much

Best regards,
by m_tanawat
6 months ago
Forum: Syntax
Topic: Fill in equation_Basic IO model
Replies: 1
Views: 140

Re: Fill in equation_Basic IO model

Above problem might not be difficult.
But your help will help me identify the key concept to code the equation more efficiently.

Thank you very much.
by m_tanawat
6 months ago
Forum: Syntax
Topic: Fill in equation_Basic IO model
Replies: 1
Views: 140

Fill in equation_Basic IO model

Hi, I am practicing building IO model by using GAMS. Could you please help me fill me the equation to let model calculate x1,x2,x3,m,w,depr and profit per sector. As I know, I have to use the equation x=Ax+d. But how to code above eqn in to program is a problem. I try to do it many times but still c...
by m_tanawat
6 months ago
Forum: Syntax
Topic: dynamic growth syntax without max/min solve statement
Replies: 1
Views: 171

dynamic growth syntax without max/min solve statement

Hi, I am trying to do future projection of population. Understand that GAMS modeling standard requires model and solve statement. I am not sure if in my case I do not want to maximize or minimize anything. I just want GAMS to calculate future population. How can I complete below program? Set t / 198...
by m_tanawat
6 months ago
Forum: Modeling
Topic: Dimension different in GAMS error message
Replies: 2
Views: 191

Re: Dimension different in GAMS error message

1) Understand that GAMS can only maximize one dimension variable. In my case, I try to do maximize one dimension varibale as well so I give syntax CCntry("NETHERL"). I want to confirm is this the correct syntax? If not how can I handle this situation? 2) When I wan to maximize 2 variable in GAMS. I ...
by m_tanawat
6 months ago
Forum: Modeling
Topic: Dimension different in GAMS error message
Replies: 2
Views: 191

Dimension different in GAMS error message

Hi, I tried to run acid model and found one error. Error148 Dimension different - The symbol is referenced with more/less indices as declared This occurred only when I change the solve statement from minimizing C to minimizing Ccntry("NETHERL"). Could you please advise how to fix it? Thank you in ad...
by m_tanawat
6 months ago
Forum: Syntax
Topic: Dimension different error
Replies: 0
Views: 110

Dimension different error

Hi, I tried to run acid model and found one error. Error148 Dimension different - The symbol is referenced with more/less indices as declared This occurred only when I change the solve statement from minimizing C to minimizing Ccntry("NETHERL"). Could you please advise? ************************** SE...