Search found 8 matches

by sinagilassi
6 years ago
Forum: Modeling
Topic: Neos Server using BARON
Replies: 0
Views: 2442

Neos Server using BARON

Hi, I run a model through neos-server. I chose BARON solver to find the global optimum but I got messages with star sign on the left, please see the attachment. What does it mean? Are these points local optimum? and how can I use them? If one of them is the global optimum how I see the rest of resul...
by sinagilassi
6 years ago
Forum: Syntax
Topic: Equation based on set number
Replies: 2
Views: 3020

Re: Equation based on set number

Hi Renger, Thank you for your help Hi This is not a problem for Gams. For i = 2, it writes the equation as Z1(i).. X_V_ce("2") =e= 0; If you want another formulation for this case, you could use the cardinality of set i (the number of elements): Z1(i).. X_V_ce(i) =e= X_V_ce(i+1)$(ord(i) ne...
by sinagilassi
6 years ago
Forum: Syntax
Topic: Equation based on set number
Replies: 2
Views: 3020

Equation based on set number

Hi,

I defined a set and a parameter as

Code: Select all

Sets i /1, 2/;   

Positive Variable X_V_ce(i);
 
one of the constraints is

Code: Select all


Z1(i).. X_V_ce(i) =e= X_V_ce(i+1) + ....

How it can be defined, i cannot be set i+1 !!

What can I do to add 1 or 2 to an element?

Regards
by sinagilassi
6 years ago
Forum: Modeling
Topic: call external function
Replies: 6
Views: 5305

Re: call external function

thank you, Micheal, for your time. I saw the code and even your codes. I should confess GAMS is the most complicated programming languages I have ever seen! Unfortunately, it's like decoding... even the guides don't provide any clear explanation. I don't know why. When I google GAMS tutorial or sour...
by sinagilassi
6 years ago
Forum: Modeling
Topic: call external function
Replies: 6
Views: 5305

Re: call external function

When I changed the code: $FuncLibIn gams_fun mylib\gamsfun I got this: Entry not found: QueryLibrary in mylib\gamsfun.dll again the file is not loaded properly. GAMS can work with a DLL (but this needs to provide a special function API). See external equations (https://www.gams.com/24.9/docs/UG_Exte...
by sinagilassi
6 years ago
Forum: Modeling
Topic: call external function
Replies: 6
Views: 5305

Re: call external function

$FuncLibIn gams_fun mylib/gamsfun the dll file is "gamsfun.dll" and the error is: Problem occured when trying to load mylib/gamsfun64.ll I don't know why 64 is added at the end! GAMS can work with a DLL (but this needs to provide a special function API). See external equations (https://www...
by sinagilassi
6 years ago
Forum: Modeling
Topic: call external function
Replies: 6
Views: 5305

Re: call external function

Michael, The function - callfun(x2) - get x2 and then return an int value. It has no derivation. I tried to make dll in c# like this Public static int callfun(int x_in) { x_in = x_in + 1 Return x_in } When I imported it through $Funlibin, I encountered a problem regarding loading error. In guideline...
by sinagilassi
6 years ago
Forum: Modeling
Topic: call external function
Replies: 6
Views: 5305

call external function

Hi,

I want to define a constraint like this:

x1 + callfun(x2) =E= 1;

callfun(x2) is a function exists in MATLAB directory.

Is it possible to call it from GAMS?

if no, MATLAB code can be converted to C# (dll) and then the dll can be used as an external function?

Thank you