MyMCTS.h

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#pragma once 

#include "PartialMCTSNode.h"
#include "ParallelTempering.h"
#include "MCMCChain.h"

class MyMCTS : public PartialMCTSNode<MyMCTS, MyHypothesis> {
    using Super = PartialMCTSNode<MyMCTS, MyHypothesis>;
    using Super::Super;

public:
    MyMCTS(MyMCTS&&) { assert(false); } // must be defined but not used

    virtual generator<MyHypothesis&> playout(MyHypothesis& current) override {
        // define our own playout here to call our callback and add sample to the MCTS
        
        MyHypothesis h0 = current; // need a copy to change resampling on 
        for(auto& n : h0.get_value() ){
            n.can_resample = false;
        }

        h0.complete(); // fill in any structural gaps   
        
        // check to see if we have no gaps and no resamples, then we just run one sample. 
        std::function no_resamples = +[](const Node& n) -> bool { return not n.can_resample;};
        if(h0.count_constants() == 0 and h0.get_value().all(no_resamples)) {
            this->process_evaluable(current);
            co_yield h0;
        }
        else {
            
            double best_posterior = -infinity; 
            long steps_since_best = 0;
            
            // else we run vanilla MCMC
            MCMCChain chain(h0, data);
//          ParallelTempering chain(h0, &mydata, 10, 100.0 ); 
            for(auto& h : chain.run(InnerControl()) | burn(BURN_N) | thin(FleetArgs::inner_thin) ) {
                
                // return if we haven't improved in howevermany samples. 
                if(h.posterior > best_posterior) {
                    best_posterior = h.posterior;
                    steps_since_best = 0;
                }
                
                this->add_sample(h.posterior); 
                co_yield h;

                //
                if(steps_since_best > 100000) break; 
            }

        }
    }
    
};