Fix on the Mesh interpolation

Author: mesonepigreco

Modules/Ensemble.py

@@ -2309,7 +2309,7 @@ def get_free_energy(self, return_error = False):
         return free_energy
 
 
-    def get_free_energy_interpolating(self, target_supercell, support_dyn_coarse = None, support_dyn_fine = None, error_on_imaginary_frequency = True, return_error = False):
+    def get_free_energy_interpolating(self, target_supercell, support_dyn_coarse = None, support_dyn_fine = None, error_on_imaginary_frequency = True, return_error = False, use_lo_to_splitting = False):
         """
         GET THE FREE ENERGY IN A BIGGER CELL
         ====================================
@@ -2337,6 +2337,7 @@ def get_free_energy_interpolating(self, target_supercell, support_dyn_coarse = N
             return_error : bool
                As the normal get_free_energy, if this flag is True, the stochastic error is returned.
 
+
         Returns
         -------
             free_energy : float
@@ -2354,17 +2355,17 @@ def get_free_energy_interpolating(self, target_supercell, support_dyn_coarse = N
 
 
         # Interpolate the dynamical matrix
-        if support_dyn_fine is not None:
-            new_dyn = self.current_dyn.Interpolate( self.current_dyn.GetSupercell(),
-                                                    target_supercell,
-                                                    support_dyn_coarse,
-                                                    support_dyn_fine)
+        if not use_lo_to_splitting:
+            if support_dyn_fine is not None:
+                new_dyn = self.current_dyn.Interpolate( self.current_dyn.GetSupercell(),
+                                                        target_supercell,
+                                                        support_dyn_coarse,
+                                                        support_dyn_fine)
+            else:
+                new_dyn = self.current_dyn.Interpolate( self.current_dyn.GetSupercell(),
+                                                        target_supercell)
         else:
-            new_dyn = self.current_dyn.Interpolate( self.current_dyn.GetSupercell(),
-                                                    target_supercell)
-
-        #else:
-        #    new_dyn = self.current_dyn.InterpolateMesh(target_supercell, lo_to_splitting = True)
+            new_dyn = self.current_dyn.InterpolateMesh(target_supercell, lo_to_splitting = True)
 
         #print("dyn after interpolation:", new_dyn.GetSupercell())
 

Modules/SchaMinimizer.py

@@ -216,6 +216,7 @@ def __init__(self, ensemble = None, root_representation = "normal",
 
         # Setup the meaningful_factor
         self.meaningful_factor = meaningful_factor
+        self.abs_conv_thr = 1e-8 # Below this number the minimization is considered converged
 
         # Setup the minimization algorithm
         self.minimization_algorithm = minimization_algorithm
@@ -935,6 +936,7 @@ def print_info(self):
         print (" number of configurations = ", self.ensemble.N)
         print (" max number of steps (infinity if negative) = ", self.max_ka)
         print (" meaningful factor = ", self.meaningful_factor)
+        print (" absolute convergence threshold = ", self.abs_conv_thr)
         print (" gradient to watch (for stopping) = ", self.gradi_op)
         print (" Kong-Liu minimum effective sample size = ", self.ensemble.N * self.kong_liu_ratio)
         print (" (Kong-Liu ratio = ", self.kong_liu_ratio, ")")
@@ -1617,6 +1619,11 @@ def check_stop(self, timer=None):
         gc_cond = (last_gc < last_gc_err * self.meaningful_factor)
         gw_cond = (last_gw < last_gw_err * self.meaningful_factor)
 
+        # Add a condition on the absolute value of the gradient
+        # (For perfectly harmonic systems, the error goes to zero)
+        gc_cond = gc_cond or (last_gc < self.abs_conv_thr)
+        gw_cond = gw_cond or (last_gw < self.abs_conv_thr)
+
         total_cond = False
 
         if gc_cond: