added flag to save json log file and improved trajectory preparation

src/molearn/data/prepare.py

@@ -145,7 +145,8 @@ def read_traj(self) -> None:
             top0 = None
             ucell0 = None
             for ct, (trp, top) in enumerate(zip(self.traj_path, self.topo_path)):
-                print(f"\tLoading {os.path.basename(trp)}")
+                if self.verbose:
+                    print(f"\tLoading {os.path.basename(trp)}")
                 loaded = None
                 try:
                     # do not enforce topology file on this formats
@@ -171,24 +172,38 @@ def read_traj(self) -> None:
                     loaded.unitcell_vectors = ucell0
                 multi_traj.append(loaded)
             self.traj = md.join(multi_traj)
+        # Recenter and apply periodic boundary
+        if self.image_mol:
+            try:
+                if self.verbose:
+                    print("Imaging faild - retrying with supplying anchor molecules")
+                self.traj.image_molecules(inplace=True)
+            except ValueError:
+                try:
+                    self.traj.image_molecules(
+                        inplace=True,
+                        anchor_molecules=[set(self.traj.topology.residue(0).atoms)],
+                    )
+                except ValueError as e:
+                    print(
+                        f"Unable to image molecule due to '{e}' - will just recenter it"
+                    )
+            self.traj.superpose(self.traj[0])
+        # maybe not needed after image_molecules
+        self.traj.center_coordinates()
         # converts ELEMENT names from eg "Cd" -> "C" to avoid later complications
         topo_table, topo_bonds = self.traj.topology.to_dataframe()
         topo_table["element"] = topo_table["element"].apply(
             lambda x: x if len(x.strip()) <= 1 else x.strip()[0]
         )
+        if self.verbose:
+            print("Saving new topology")
         self.traj.topology = md.Topology.from_dataframe(topo_table, topo_bonds)
         # save new topology
         self.traj[0].save_pdb(
             os.path.join(self.outpath, f"./{self.traj_name}_NEW_TOPO.pdb")
         )
-        # Recenter and apply periodic boundary
-        if self.image_mol:
-            try:
-                self.traj.image_molecules(inplace=True)
-            except ValueError as e:
-                print(f"Unable to image molecule due to '{e}' - will just recenter it")
-        # maybe not needed after image_molecules
-        self.traj.center_coordinates()
+
         n_frames = self.traj.n_frames
         # which index separated indices from training and test dataset
         self.test_border = int(n_frames * (1.0 - self.test_size))
@@ -205,6 +220,8 @@ def read_traj(self) -> None:
         atom_indices = [
             a.index for a in train_traj.topology.atoms if a.element.symbol != "H"
         ]
+        if self.verbose:
+            print("Calculating disance matrix")
         # distance matrix between all frames
         self.traj_dists = np.empty((n_train_frames, n_train_frames))
         for i in range(n_train_frames):

src/molearn/trainers/trainer.py

@@ -31,10 +31,11 @@ class Trainer:
 
     """
 
-    def __init__(self, device=None, log_filename="log_file.dat"):
+    def __init__(self, device=None, log_filename="log_file.dat", json_log=False):
         """
         :param torch.Device device: if not given will be determinined automatically based on torch.cuda.is_available()
         :param str log_filename: (default: 'default_log_filename.json') file used to log outputs to
+        :param bool json_log: True to use json.dump to save the log file
         """
         if not device:
             self.device = (
@@ -52,6 +53,7 @@ def __init__(self, device=None, log_filename="log_file.dat"):
         self.verbose = True
         self.log_filename = "default_log_filename.csv"
         self.scheduler_key = None
+        self.json_log = json_log
 
     def get_network_summary(self):
         """
@@ -151,17 +153,22 @@ def log(self, log_dict, verbose=None):
                     print(f"{k: <{max_key_len+1}}: {v:.6f}")
             print()
 
-        # create header if file doesn't exist => first epoch
-        if not os.path.isfile(self.log_filename):
-            with open(self.log_filename, "a") as f:
-                f.write(f"{','.join([str(k) for k in log_dict.keys()])}\n")
+        if not self.json_log:
+            # create header if file doesn't exist => first epoch
+            if not os.path.isfile(self.log_filename):
+                with open(self.log_filename, "a") as f:
+                    f.write(f"{','.join([str(k) for k in log_dict.keys()])}\n")
 
-        with open(self.log_filename, "a") as f:
-            # just try to format if it is not a Failure
-            if "Failure" not in log_dict.values():
-                f.write(f"{','.join([str(v) for v in log_dict.values()])}\n")
-            else:
-                dump = json.dumps(log_dict)
+            with open(self.log_filename, "a") as f:
+                # just try to format if it is not a Failure
+                if "Failure" not in log_dict.values():
+                    f.write(f"{','.join([str(v) for v in log_dict.values()])}\n")
+                else:
+                    dump = json.dumps(log_dict)
+                    f.write(dump + "\n")
+        else:
+            dump = json.dumps(log_dict)
+            with open(self.log_filename, "a") as f:
                 f.write(dump + "\n")
 
     def scheduler_step(self, logs):