# How do I use multi-parameters in my optimization problem for fminunc?

4 次查看（过去 30 天）
Satyajit Ghosh2021-10-9

So, right now, I am performing an optimization with respect to all elements of 'A' matrix using below command.
[Aopt,fopt]=fminunc(@(A)myObjective(A,N33,p1,v,limit,n),A0,options);
But now I want an extra parameter (x) to be used for optimization also. This will be a scalar. Is the code will look like this?
[Aopt,fopt]=fminunc(@(A,x)myObjective(A,x,N33,p1,v,limit,n),A0,x0,options);

### 采纳的回答

Matt J 2021-10-10

You can do something like that in the problem-based framework.
A=optimvar('A',N,3);
x=optimvar('x',1);
fun=fcn2optimexpr( @(A,x)myObjective(A,x,N33,p1,v,limit,n) , A x)
sol0.A=... %initial A0
sol0.x=... %initial x0
sol=solve( optimproblem('Objective',fun) , sol0,options);
##### 1 个评论显示隐藏 无
Satyajit Ghosh 2021-10-26
After implementing above code segment, I am getting this error.
Error using optim.internal.problemdef.ProblemImpl/solveImpl
Expected a string scalar or character vector for the parameter name
Error in optim.problemdef.OptimizationProblem/solve
Error in Optimization_FINAL.m (line 145)
sol=solve(optimproblem('Objective',fun),sol0,options);

### 更多回答（1 个）

John D'Errico 2021-10-9
No. It won't look like that. fminunc cannot somehow magically know how you intend the inputs to be used. Computers cannot read your mind. Well, not yet, but the mind reading toolbox is still under beta test.
Functions assume the input paraneters are as they are defined in the help.
If you want to optimize both A and x, then you need to treat all parameters in one vector (or array). Split them apart inside your objective function.

R2018b

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by