calculate_test_estimator.m

function [epsilon_test,epsilon_max,rb_sim_av_time,std_dev] = calculate_test_estimator(model, reduced_data)
  %
  % computes run-times and error estimators for a test sample of size
  % 'N_test = 10' and collects statistical data on these magnitudes.
  %
  % Additionally, a scatter plot of the errors over the first two dimensions of
  % the parameter domain is generated.
  % 
  % Return values:
  %  epsilon_test: mean value of error estimators
  %  epsilon_max:  max value of error estimators
  %  rb_sim_av_time: mean run-time of reduced simulations
  %  std_dev:        standard deviation of error estimators
  %
    display('Calculating estimated test error');
    N_test=25;%amount of Tests
    rand('state',model.random_seed);
    
    if isfield(model,'N_test')
        N_test = model.N_test;
    end
    disp(['Nr. of Test points: ',num2str(N_test)]);
    random_mu = rand_uniform(N_test, model.mu_ranges);
    
    error_max=0;
    rb_sim_time=0;
    est_error=zeros(1,N_test);
    for i=1:N_test
       %Choose a mu from range by random choice
       mu = random_mu(:,i);
       model = set_mu(model,mu);
       %perform a reduced simulation and take the estiamated error of last
       %time step
       rb_sim_timer = tic;
       rb_sim_data = rb_simulation(model, reduced_data);
       rb_sim_time = rb_sim_time + toc(rb_sim_timer);
       %add error to total error
       if isfield(rb_sim_data,'DeltaX')
        est_error(i) = rb_sim_data.DeltaX(end);
       elseif isfield(rb_sim_data,'Delta')
        est_error(i) = rb_sim_data.Delta(end);
       end
       
       if~(isfield(model,'verbose'))
           model.verbose = 20;
       end
       
       
       if(model.verbose>5)
           if (mod(i,10)==0)
            disp('...')
           end
       end
    end
   
    
    %calculate average estimated error
   epsilon_test = sum(est_error)/N_test;
   epsilon_max=max(est_error);
   rb_sim_av_time = rb_sim_time/N_test;
   std_dev=std(est_error);
   %Visualisation of error map on parameter domain
   
   sizeMu = size(random_mu);
   if (sizeMu(1) == 3)
       %figure;
       % scatter3(random_mu(1,:),random_mu(2,:), random_mu(3,:),40,est_error,'filled');
       %colorbar;
   elseif (sizeMu(1) ==2)
       figure;
    scatter(random_mu(1,:),random_mu(2,:),40,est_error,'filled');
    colorbar;
   end
   
end