[Ipopt] intermediate_callback Method

[Stefan Vigerske]

Hi,

>       I am using the C++ version of Ipopt. I have a class which inherits
> from TNLP and I provide an implementation for *intermediate_callback*  in my
> derived class. But the execution never reaches my implementation.
> 
>       Can someone suggest something? Is there some option that needs to be
> set?

It should be called at each iteration automatically.
Maybe you missed something in the signature of your implementation of
intermediate_callback. It has many arguments. If you missed something,
then the compiler would not recognize that you attempted to overwrite
the one from TNLP.

It should be
     bool intermediate_callback(AlgorithmMode mode,
                                       Index iter, Number obj_value,
                                       Number inf_pr, Number inf_du,
                                       Number mu, Number d_norm,
                                       Number regularization_size,
                                       Number alpha_du, Number alpha_pr,
                                       Index ls_trials,
                                       const IpoptData* ip_data,
                                       IpoptCalculatedQuantities* ip_cq)

Best,
Stefan