sdpsetting for optimization problem

[Negar Tabibpour]

hello 

i want to solve an optimization problem ,but I do not know what order should I use for sdpsetting?

[Johan Löfberg]

There is no order, just field followed by value

https://yalmip.github.io/command/sdpsettings/

[Negar Tabibpour]

i need a solver to solve operation optimization problem in yalmip ,CPLEX is used before this ,but i cant download that .what is other solvers to solve operation optimization problem?

[Johan Löfberg]

Gurobi, mosek, scip are good integer solvers

https://yalmip.github.io/tags/#mixed-integer-linear-programming-solver

[Negar Tabibpour]

Hi, 

Thank you. Now I get a new error in my optimization code and I am not sure how to solve it,

When I run my mfile script the following error comes up

>> projectFinall

Error using solvesdp (line 98)

First argument (F) should be a constraint object.

Error in optimize (line 31)

varargout{:} = solvesdp(varargin{:});

Error in projectFinall (line 110)

sol = optimize(Constraint,Objective,Options);

 

[Johan Löfberg]

Well obviously you are not sending a constraint as the first argument in solvesdp (which is obsolete, it is called optimize)

[Negar Tabibpour]

Thank you for all your help.

The error that matlab is shows has something to do with the way that the constraints are written. I tried to rewrite my code based on Matlab recommendation but it still does not work, can you take a look at the script please ?

[Johan Löfberg]

What script?

[Johan Löfberg]

Constraints=[ 1 > == Spurt+Ssellt                    ↑

Error: Unexpected MATLAB operator.

Please the the basic tutorial on how constraints are defined

https://yalmip.github.io/tutorial/basics/

[Johan Löfberg]

And your code makes no sense as all expressions in your constraints are numerical data which means all comparisons evaluates to logic data, which will causes MATLAB to terminate as it cannot concatenate numerical data of different dimensions.

Additionally, you are using strict inequalities > which isn't allowed (it runs, but YALMIP will tell you that you shouldn't use it as it doesn't support it really. Everything is non-strict in solvers)

[Johan Löfberg]

It also looks like you think you can solve this using a linear solver (as you appear to want to use cplex), but the problem is nonlinear as you have nonconvex bilinear constraints.

[Negar Tabibpour]

hello ,Thanks a lot for your help again,it means a lot to me .i was able to solve the issues my coding had with your hints,however, as I remember ,you said the problem is nonlinear while i was using linear solvers and i didn't make a change .i am now getting some errors when i try to run the m-file.I have attached the m-file for you to take a look at.Please let me know how to fix them,thanks.

[Johan Löfberg]

Constraints is just a list ones, so the code makes no sense

[Johan Löfberg]

and your options make no sense.

Options = sdpsettings('solver','cplex','verbos','1','solver','bmibnb');


You want to use both cplex and bmibnb?. And it should be 'verbose',1

[Negar Tabibpour]

some of the errors matlab gave me as regarding the constraints that i  had deleted them.

and unfortunately i dont have enough knowledge about sdpsetting and i just wanted to test these settings.

[Johan Löfberg]

so you've understood now where the problem is?

[Negar Tabibpour]

No,can you explain more or refine the code?

[Johan Löfberg]

This is your problem

>> Constraints

Constraints =

  Columns 1 through 15

     1     1     1     1     1     1     1     1     1     1     1     1     1     1     1

  Columns 16 through 26

     1     1     1     1     1     1     1     1     1     1     0

[Negar Tabibpour]

Now what should i do to resolve this problem

[Johan Löfberg]

1. Understand which variable is crazy (Constraints)
2. Figure out on which line that variable is defined
3. Look at the objects which you use to define it
4. Understand why those objects look like they do, and fix that

[Negar Tabibpour]

Hi again, i changed my constraints and now i know what was the problem with my coding. I have fixed the problem by using Sedumi and sdpt3  solvers. In the meanwhile though, i am not sure what the major differences are between these two solvers

[Johan Löfberg]

For the casual user, no difference.

[Negar Tabibpour]

thank you very much.