Hi Fred,

Many thanks for your reply.

I totally understand it now.

Best regards,

## Search found 13 matches

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

- 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...

- 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 ...

- 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,

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,

- 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.

But your help will help me identify the key concept to code the equation more efficiently.

Thank you very much.

- 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...

- 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...

- 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 ...

- 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...

- 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...