Name

temp_law_fsa — The Szu and Hartley Fast simulated annealing

Calling Sequence

T_out = temp_law_fsa(T_in,step_mean,step_var,temp_stage,n,param)

Parameters

T_in

the temperature at the current stage

step_mean

the mean value of the objective function computed during the current stage

step_var

the variance value of the objective function computed during the current stage

temp_stage

the index of the current temperature stage

n

the dimension of the decision variable (the x in f(x))

param

not used for this temperature law

T_out

the temperature for the temperature stage to come

Description

  • This function implements the Fast simulated annealing of Szu and Hartley.

Examples

  function y = rastrigin(x)
    y = x(1)^2+x(2)^2-cos(12*x(1))-cos(18*x(2));
  endfunction

  x0 = [-1, -1];
  Proba_start = 0.8;
  It_intern = 1000;
  It_extern = 30;
  It_Pre    = 100;

  printf('SA: the FSA algorithm\n');

  T0 = compute_initial_temp(x0, rastrigin, Proba_start, It_Pre, neigh_func_default);
  printf('Initial temperatore T0 = %f\n', T0);

  [x_opt, f_opt, sa_mean_list, sa_var_list, temp_list] = optim_sa(x0, rastrigin, It_extern, It_intern, T0, Log = %T, temp_law_fsa, neigh_func_fsa);

  printf('optimal solution:\n'); disp(x_opt);
  printf('value of the objective function = %f\n', f_opt);

  scf();
  subplot(2,1,1);
  xtitle('Fast simulated annealing','Iteration','Mean / Variance');
  t = 1:length(sa_mean_list);
  plot(t,sa_mean_list,'r',t,sa_var_list,'g');
  legend(['Mean','Variance']);
  subplot(2,1,2);
  xtitle('Temperature evolution','Iteration','Temperature');
  plot(t,temp_list,'k-');
  

See Also

optim_sa , temp_law_huang , neigh_func_default

Authors

collette

Yann COLLETTE ([email protected])