MATLAB: MATLAB Coder Error – optimset Unrecognized parameter name: ‘GradObj’

code generationMATLABmatlab coderoptimization

Hi,
I'm trying to generate C code of a function using MATLAB Coder but I am getting the following error when generating MEX:
Unrecognized parameter name: 'GradObj'
Full instruction is:
optionsNLP = optimset('GradObj', 'off', 'GradConstr', 'off', ...
        'DerivativeCheck', 'off', 'Display', 'iter', 'TolX', 1e-9, ...
        'TolFun', 1e-9, 'TolCon', 1e-9, 'MaxFunEval', 300, 'DiffMinChange', 1e-5);
It is working when I run the MATLAB script directly.
I am thinking that maybe it can not be generated because a Toolbox is required to use the GradObj parameter?
Does anyone knows a workaround if any?
Thanks.
Vadim

Best Answer

Hi Vadim,
For generating C code for fmincon (or lsqnonlin, etc.) via MATLAB Coder, we require that you use the optimoptions function to set options. See the requirements in this documentation page.
Also, an important note is that only the SQP algorithm of fmincon is supported for C code generation.
The equivalent code for your example is as follows
optionsNLP = optimoptions('fmincon','Algorithm','sqp','SpecifyObjectiveGradient', false, ...
   'CheckGradients', false, 'Display', 'iter', 'StepTolerance', 1e-9, 'FunctionTolerance', 1e-9, ...
         'ConstraintTolerance', 1e-9, 'MaxFunctionEvaluations', 300, 'DiffMinChange', 1e-5);
Related Question