Programmatically testing whether a variable is an optimoptions object

I was wondering if there was something like an isoptimoptions function that could be used to test in general whether a variable was generated by optimoptions(). The isa command alone will not seem to do it, because optimoptions objects occupy separate classes, depending on which solver the object was generated for.

>> opts1=optimoptions('lsqnonlin');  
>> opts2=optimoptions('linprog');  

>> whos opts1 opts2
  Name       Size            Bytes  Class                      Attributes

  opts1      1x1             29913  optim.options.Lsqnonlin              
  opts2      1x1             14775  optim.options.Linprog                

The following user-defined command seems to work, but I'm wondering if there are more direct alternatives,

function bool=isaoptimoptions(opts)
  bool = startsWith(class(opts),'optim.options')
end

[Guillaume]

I don't have the toolbox so can't test, but don't they all derive from the same (possibly abstract) base class?

[Matt J]

How would we test that?

[Guillaume]

superclasses(obj)

will tell you the base classes (if any). isa on the base class would work.

[Matt J]

Theyhave several parent classes, but those I've checked all seem to have 'optim.options.SolverOptions' as a parent in common.

>> superclasses(optimoptions('linprog'))

Superclasses for class optim.options.Linprog:

    optim.options.MultiAlgorithm
    optim.options.SolverOptions
    matlab.mixin.CustomDisplay

>> superclasses(optimoptions('intlinprog'))

Superclasses for class optim.options.Intlinprog:

    optim.options.SingleAlgorithm
    optim.options.SolverOptions
    matlab.mixin.CustomDisplay

>> superclasses(optimoptions('lsqlin'))

Superclasses for class optim.options.Lsqlin:

    optim.options.MultiAlgorithm
    optim.options.SolverOptions
    matlab.mixin.CustomDisplay

Answer 1

[Guillaume]

"those I've checked all seem to have 'optim.options.SolverOptions' as a parent in common."

In that case:

isa(opts, 'optim.options.SolverOptions')

edit:

Strangely enough the base class optim.options.SolverOptions is part of base matlab (or a toolbox I've got even though I've haven't got the optimisation toolbox) and available as an m file.

The comment in the m file does say that this is the "base class for Optimization Toolbox options", so yes, the above is what you want.

[Matt J]

Yeah, I guess that makes sense. It would be nice if it were documented in the toolbox that this will always be the root class ...

Answer 2

[Luna]

Hi,

Maybe something like this helps?

metaClass = metaclass(opts1);
if contains(metaClass.Name,'optim.options')
  disp('This is a optim.options object.')
else
end

[Matt J]

Hi Luna,

That would work, but is pretty much the same as the provisional solution mentioned in my original post.