## Search found 439 matches

- 5 days ago
- Forum: Syntax
- Topic: creation of vectors from normal distribution
- Replies:
**3** - Views:
**85**

### Re: creation of vectors from normal distribution

Hi You could search in this forum for Error 149 as strongly advised in the "Forum rules" ... 115 parameter a(i,j); 116 a(i,j)= normal(x(j,i),t(j,p)); or study the error message "149 Uncontrolled set entered as constant". You define a parameter over the sets i and j, but on the right-hand side you us...

- 5 days ago
- Forum: Archive Google Group
- Topic: two shock in two time in a loop
- Replies:
**1** - Views:
**42**

### Re: two shock in two time in a loop

Hi You can loop over the whole horizon and change the parameters for the shocks. Here some example code: set t Periods /1*20/; set sc /BAU, SHOCK/; parameter parshock(sc,t) Shock some parameters parshock(sc,t) = 0; parshock("SHOCK",t)$(t.val < 5) = 2; parshock("SHOCK",t)$(t.val > 4) = 3; loop(sc, lo...

- 5 days ago
- Forum: Modeling
- Topic: adding more constraint to gams
- Replies:
**3** - Views:
**117**

- 1 week ago
- Forum: Solvers
- Topic: Different results with zero optimality gap: MIP against SOS2
- Replies:
**2** - Views:
**144**

### Re: Different results with zero optimality gap: MIP against SOS2

Hi

Perhaps your problem has multiple solutions? You could use the solution of the first method as starting point for the second and see if the second algorithm and see if this reproduces this first solution. (the same vice versa).

Cheers

Renger

Perhaps your problem has multiple solutions? You could use the solution of the first method as starting point for the second and see if the second algorithm and see if this reproduces this first solution. (the same vice versa).

Cheers

Renger

- 1 week ago
- Forum: Modeling
- Topic: adding more constraint to gams
- Replies:
**3** - Views:
**117**

### Re: adding more constraint to gams

Hi

You could just split the constraint in:
Cheers

Renger

You could just split the constraint in:

Code: Select all

```
upperb(x).. 1.3 * w(x) =L=r(x);
lowerb(x).. r(x) =L= 1.6 * w(x);
```

Renger

- 1 week ago
- Forum: API
- Topic: how to add fromula at parameter
- Replies:
**3** - Views:
**222**

### Re: how to add fromula at parameter

Hi

You made your model non-linear as the variables C and X are multiplied with each other.

If you change your solve instruction into
it solves nicely.

Cheers

Renger

You made your model non-linear as the variables C and X are multiplied with each other.

If you change your solve instruction into

Code: Select all

```
Solve struktura using NLP maximizing f;
```

Cheers

Renger

- 1 week ago
- Forum: API
- Topic: how to add fromula at parameter
- Replies:
**3** - Views:
**222**

### Re: how to add fromula at parameter

Hi I might be missing the point, but why don't you use the profit equation as described in your question? equation profit(j) Profit equation; c(j)=E= a('T1',j) - a('N1',j) - a('N2',j) If you paste code, please use the button "</>" in the editor. It will keep the formatting. Furthermore, without the ...

- 3 weeks ago
- Forum: Syntax
- Topic: execute_load all parameters with wildcard or similar
- Replies:
**1** - Views:
**953**

### Re: execute_load all parameters with wildcard or similar

Hi THe only thing I can think of is starting the outer loop before the assignments of the default values. In your simple example: *set up all default data parameter x; loop(i, x = 0; loop(j, *manipulate parameters x=x+j Objective=E=f(i,j) solve model min Objective ) ) Cheers Renger

- 1 month ago
- Forum: Syntax
- Topic: Sum of the dynamic set
- Replies:
**2** - Views:
**184**

### Re: Sum of the dynamic set

Hi Sue

Could you write out examples of the equation you want in point 1. It is not clear to me.

Point 2: You could use a set defining which elements you don't want (e.g. set src(nt) /n3/; and write the equation q4(nt)$(not src(nt)).

Cheers

Renger

Could you write out examples of the equation you want in point 1. It is not clear to me.

Point 2: You could use a set defining which elements you don't want (e.g. set src(nt) /n3/; and write the equation q4(nt)$(not src(nt)).

Cheers

Renger

- 1 month ago
- Forum: Syntax
- Topic: Sum of Rows = Sum of Columns
- Replies:
**5** - Views:
**309**

### Re: Sum of Rows = Sum of Columns

Hi

The problem is that you use both i and j in two different ways: as an index for the equation and as summation index.

You need an alias:
This resolves the confusion on what to do with "i" and "j".

Cheers

Renger

The problem is that you use both i and j in two different ways: as an index for the equation and as summation index.

You need an alias:

Code: Select all

```
alias(i,ai), (j,aj);
eq6(i,j).. sum(ai, Q(ai,j)) =e= sum(aj, Q(i,aj));
```

Cheers

Renger