Simplify variables: step, epoch, max_epochs, min_epochs (#589)

README.md

@@ -154,16 +154,16 @@ use something other than tensorboard).
 Here are more advanced examples
 ```python   
 # train on cpu using only 10% of the data (for demo purposes)
-trainer = Trainer(max_num_epochs=1, train_percent_check=0.1)
+trainer = Trainer(max_epochs=1, train_percent_check=0.1)
 
 # train on 4 gpus (lightning chooses GPUs for you)
-# trainer = Trainer(max_num_epochs=1, gpus=4, distributed_backend='ddp')  
+# trainer = Trainer(max_epochs=1, gpus=4, distributed_backend='ddp')  
 
 # train on 4 gpus (you choose GPUs)
-# trainer = Trainer(max_num_epochs=1, gpus=[0, 1, 3, 7], distributed_backend='ddp')   
+# trainer = Trainer(max_epochs=1, gpus=[0, 1, 3, 7], distributed_backend='ddp')   
 
 # train on 32 gpus across 4 nodes (make sure to submit appropriate SLURM job)
-# trainer = Trainer(max_num_epochs=1, gpus=8, num_gpu_nodes=4, distributed_backend='ddp')
+# trainer = Trainer(max_epochs=1, gpus=8, num_gpu_nodes=4, distributed_backend='ddp')
 
 # train (1 epoch only here for demo)
 trainer.fit(model)

pl_examples/full_examples/imagenet/imagenet_example.py

@@ -234,7 +234,7 @@ def main(hparams):
     trainer = pl.Trainer(
         default_save_path=hparams.save_path,
         gpus=hparams.gpus,
-        max_num_epochs=hparams.epochs,
+        max_epochs=hparams.epochs,
         distributed_backend=hparams.distributed_backend,
         use_amp=hparams.use_16bit
     )

pytorch_lightning/core/lightning.py

@@ -694,10 +694,10 @@ def configure_optimizers(self):
         """
         raise NotImplementedError
 
-    def optimizer_step(self, epoch_idx, batch_idx, optimizer, optimizer_idx, second_order_closure=None):
+    def optimizer_step(self, epoch, batch_idx, optimizer, optimizer_idx, second_order_closure=None):
         """Do something instead of the standard optimizer behavior
 
-        :param int epoch_idx:
+        :param int epoch:
         :param int batch_idx:
         :param optimizer:
         :param optimizer_idx:

pytorch_lightning/logging/__init__.py

@@ -52,7 +52,7 @@ def log_hyperparams(self, params):
             pass
 
         @rank_zero_only
-        def log_metrics(self, metrics, step_idx):
+        def log_metrics(self, metrics, step):
             # metrics is a dictionary of metric names and values
             # your code to record metrics goes here
             pass

pytorch_lightning/logging/base.py

@@ -21,11 +21,11 @@ class LightningLoggerBase(object):
     def __init__(self):
         self._rank = 0
 
-    def log_metrics(self, metrics, step_idx):
+    def log_metrics(self, metrics, step):
         """Record metrics.
 
         :param float metric: Dictionary with metric names as keys and measured quanties as values
-        :param int|None step_idx: Step number at which the metrics should be recorded
+        :param int|None step: Step number at which the metrics should be recorded
         """
         raise NotImplementedError()
 

pytorch_lightning/logging/comet.py

@@ -145,13 +145,13 @@ def log_hyperparams(self, params):
         self.experiment.log_parameters(vars(params))
 
     @rank_zero_only
-    def log_metrics(self, metrics, step_idx=None):
+    def log_metrics(self, metrics, step=None):
         # Comet.ml expects metrics to be a dictionary of detached tensors on CPU
         for key, val in metrics.items():
             if is_tensor(val):
                 metrics[key] = val.cpu().detach()
 
-        self.experiment.log_metrics(metrics, step=step_idx)
+        self.experiment.log_metrics(metrics, step=step)
 
     @rank_zero_only
     def finalize(self, status):

pytorch_lightning/logging/mlflow.py

@@ -68,15 +68,15 @@ def log_hyperparams(self, params):
             self.experiment.log_param(self.run_id, k, v)
 
     @rank_zero_only
-    def log_metrics(self, metrics, step_idx=None):
+    def log_metrics(self, metrics, step=None):
         timestamp_ms = int(time() * 1000)
         for k, v in metrics.items():
             if isinstance(v, str):
                 logger.warning(
                     f"Discarding metric with string value {k}={v}"
                 )
                 continue
-            self.experiment.log_metric(self.run_id, k, v, timestamp_ms, step_idx)
+            self.experiment.log_metric(self.run_id, k, v, timestamp_ms, step)
 
     def save(self):
         pass

pytorch_lightning/logging/test_tube.py

@@ -76,10 +76,10 @@ def log_hyperparams(self, params):
         self.experiment.argparse(params)
 
     @rank_zero_only
-    def log_metrics(self, metrics, step_idx=None):
+    def log_metrics(self, metrics, step=None):
         # TODO: HACK figure out where this is being set to true
         self.experiment.debug = self.debug
-        self.experiment.log(metrics, global_step=step_idx)
+        self.experiment.log(metrics, global_step=step)
 
     @rank_zero_only
     def save(self):

pytorch_lightning/trainer/logging.py

@@ -43,7 +43,7 @@ def log_metrics(self, metrics, grad_norm_dic):
 
         # log actual metrics
         if self.proc_rank == 0 and self.logger is not None:
-            self.logger.log_metrics(scalar_metrics, step_idx=self.global_step)
+            self.logger.log_metrics(scalar_metrics, step=self.global_step)
             self.logger.save()
 
     def add_tqdm_metrics(self, metrics):

pytorch_lightning/trainer/trainer.py

@@ -72,8 +72,8 @@ def __init__(
             accumulate_grad_batches=1,
             max_nb_epochs=None,  # backward compatible, todo: remove in v0.8.0
             min_nb_epochs=None,  # backward compatible, todo: remove in v0.8.0
-            max_num_epochs=1000,
-            min_num_epochs=1,
+            max_epochs=1000,
+            min_epochs=1,
             train_percent_check=1.0,
             val_percent_check=1.0,
             test_percent_check=1.0,
@@ -111,8 +111,8 @@ def __init__(
         :param int check_val_every_n_epoch: check val every n train epochs
         :param bool fast_dev_run: runs full iteration over everything to find bugs
         :param int accumulate_grad_batches: Accumulates grads every k batches
-        :param int max_num_epochs:
-        :param int min_num_epochs:
+        :param int max_epochs:
+        :param int min_epochs:
         :param int train_percent_check: How much of train set to check
         :param int val_percent_check: How much of val set to check
         :param int test_percent_check: How much of test set to check
@@ -158,17 +158,17 @@ def __init__(
         self.process_position = process_position
         self.weights_summary = weights_summary
         if max_nb_epochs is not None:  # Backward compatibility
-            warnings.warn("`max_nb_epochs` has renamed to `max_num_epochs` since v0.5.0"
+            warnings.warn("`max_nb_epochs` has renamed to `max_epochs` since v0.5.0"
                           " and will be removed in v0.8.0", DeprecationWarning)
-            if not max_num_epochs:  # in case you did not set the proper value
-                max_num_epochs = max_nb_epochs
-        self.max_num_epochs = max_num_epochs
+            if not max_epochs:  # in case you did not set the proper value
+                max_epochs = max_nb_epochs
+        self.max_epochs = max_epochs
         if min_nb_epochs is not None:  # Backward compatibility
-            warnings.warn("`min_nb_epochs` has renamed to `min_num_epochs` since v0.5.0"
+            warnings.warn("`min_nb_epochs` has renamed to `min_epochs` since v0.5.0"
                           " and will be removed in v0.8.0", DeprecationWarning)
-            if not min_num_epochs:  # in case you did not set the proper value
-                min_num_epochs = min_nb_epochs
-        self.min_num_epochs = min_num_epochs
+            if not min_epochs:  # in case you did not set the proper value
+                min_epochs = min_nb_epochs
+        self.min_epochs = min_epochs
         if nb_sanity_val_steps is not None:  # Backward compatibility
             warnings.warn("`nb_sanity_val_steps` has renamed to `num_sanity_val_steps` since v0.5.0"
                           " and will be removed in v0.8.0", DeprecationWarning)
@@ -183,7 +183,7 @@ def __init__(
         self.fast_dev_run = fast_dev_run
         if self.fast_dev_run:
             self.num_sanity_val_steps = 1
-            self.max_num_epochs = 1
+            self.max_epochs = 1
             m = '''
             Running in fast_dev_run mode: will run a full train,
             val loop using a single batch

pytorch_lightning/trainer/training_loop.py

@@ -23,7 +23,7 @@
 .. code-block:: python
 
     # DEFAULT
-    trainer = Trainer(min_num_epochs=1, max_num_epochs=1000)
+    trainer = Trainer(min_epochs=1, max_epochs=1000)
 
 Early stopping
 --------------
@@ -259,17 +259,17 @@ def process_output(self, output, train):
 
     def train(self):
         # run all epochs
-        for epoch_idx in range(self.current_epoch, self.max_num_epochs):
+        for epoch in range(self.current_epoch, self.max_epochs):
             # set seed for distributed sampler (enables shuffling for each epoch)
             if self.use_ddp and hasattr(self.get_train_dataloader().sampler, 'set_epoch'):
-                self.get_train_dataloader().sampler.set_epoch(epoch_idx)
+                self.get_train_dataloader().sampler.set_epoch(epoch)
 
             # get model
             model = self.get_model()
 
             # update training progress in trainer and model
-            model.current_epoch = epoch_idx
-            self.current_epoch = epoch_idx
+            model.current_epoch = epoch
+            self.current_epoch = epoch
 
             # val can be checked multiple times in epoch
             is_val_epoch = (self.current_epoch + 1) % self.check_val_every_n_epoch == 0
@@ -294,11 +294,11 @@ def train(self):
             # .reset() doesn't work on disabled progress bar so we should check
             if not self.main_progress_bar.disable:
                 self.main_progress_bar.reset(num_iterations)
-            desc = f'Epoch {epoch_idx + 1}' if not self.is_iterable_train_dataloader else ''
+            desc = f'Epoch {epoch + 1}' if not self.is_iterable_train_dataloader else ''
             self.main_progress_bar.set_description(desc)
 
             # changing gradient according accumulation_scheduler
-            self.accumulation_scheduler.on_epoch_begin(epoch_idx, self)
+            self.accumulation_scheduler.on_epoch_begin(epoch, self)
 
             # -----------------
             # RUN TNG EPOCH
@@ -319,9 +319,9 @@ def train(self):
                 self.reduce_lr_on_plateau_scheduler.step(val_loss, epoch=self.current_epoch)
 
             # early stopping
-            met_min_epochs = epoch_idx > self.min_num_epochs
+            met_min_epochs = epoch > self.min_epochs
             if self.enable_early_stop and (met_min_epochs or self.fast_dev_run):
-                should_stop = self.early_stop_callback.on_epoch_end(epoch=epoch_idx,
+                should_stop = self.early_stop_callback.on_epoch_end(epoch=epoch,
                                                                     logs=self.callback_metrics)
                 # stop training
                 stop = should_stop and met_min_epochs

pytorch_lightning/utilities/arg_parse.py

@@ -15,8 +15,10 @@ def add_default_args(parser, root_dir, rand_seed=None, possible_model_names=None
     parser.opt_list('--accumulate_grad_batches', default=1, type=int, tunable=False,
                     help='accumulates gradients k times before applying update.'
                          ' Simulates huge batch size')
-    parser.add_argument('--max_num_epochs', default=200, type=int, help='cap epochs')
-    parser.add_argument('--min_num_epochs', default=2, type=int, help='min epochs')
+    parser.add_argument('--max_epochs', default=200, type=int,
+                        help='maximum number of epochs')
+    parser.add_argument('--min_epochs', default=2, type=int,
+                        help='minimum number of epochs')
     parser.add_argument('--train_percent_check', default=1.0, type=float,
                         help='how much of training set to check')
     parser.add_argument('--val_percent_check', default=1.0, type=float,

tests/test_amp.py

@@ -23,7 +23,7 @@ def test_amp_single_gpu(tmpdir):
     trainer_options = dict(
         default_save_path=tmpdir,
         show_progress_bar=True,
-        max_num_epochs=1,
+        max_epochs=1,
         gpus=1,
         distributed_backend='ddp',
         use_amp=True
@@ -45,7 +45,7 @@ def test_no_amp_single_gpu(tmpdir):
     trainer_options = dict(
         default_save_path=tmpdir,
         show_progress_bar=True,
-        max_num_epochs=1,
+        max_epochs=1,
         gpus=1,
         distributed_backend='dp',
         use_amp=True
@@ -69,7 +69,7 @@ def test_amp_gpu_ddp(tmpdir):
     trainer_options = dict(
         default_save_path=tmpdir,
         show_progress_bar=True,
-        max_num_epochs=1,
+        max_epochs=1,
         gpus=2,
         distributed_backend='ddp',
         use_amp=True
@@ -94,7 +94,7 @@ def test_amp_gpu_ddp_slurm_managed(tmpdir):
 
     trainer_options = dict(
         show_progress_bar=True,
-        max_num_epochs=1,
+        max_epochs=1,
         gpus=[0],
         distributed_backend='ddp',
         use_amp=True
@@ -153,7 +153,7 @@ def test_cpu_model_with_amp(tmpdir):
         default_save_path=tmpdir,
         show_progress_bar=False,
         logger=tutils.get_test_tube_logger(tmpdir),
-        max_num_epochs=1,
+        max_epochs=1,
         train_percent_check=0.4,
         val_percent_check=0.4,
         use_amp=True
@@ -175,7 +175,7 @@ def test_amp_gpu_dp(tmpdir):
     model, hparams = tutils.get_model()
     trainer_options = dict(
         default_save_path=tmpdir,
-        max_num_epochs=1,
+        max_epochs=1,
         gpus='0, 1',  # test init with gpu string
         distributed_backend='dp',
         use_amp=True

tests/test_cpu_models.py

@@ -46,7 +46,7 @@ def test_lbfgs_cpu_model(tmpdir):
 
     trainer_options = dict(
         default_save_path=tmpdir,
-        max_num_epochs=1,
+        max_epochs=1,
         print_nan_grads=True,
         show_progress_bar=False,
         weights_summary='top',
@@ -64,7 +64,7 @@ def test_default_logger_callbacks_cpu_model(tmpdir):
 
     trainer_options = dict(
         default_save_path=tmpdir,
-        max_num_epochs=1,
+        max_epochs=1,
         gradient_clip_val=1.0,
         overfit_pct=0.20,
         print_nan_grads=True,
@@ -97,7 +97,7 @@ def test_running_test_after_fitting(tmpdir):
     trainer_options = dict(
         default_save_path=tmpdir,
         show_progress_bar=False,
-        max_num_epochs=1,
+        max_epochs=1,
         train_percent_check=0.4,
         val_percent_check=0.2,
         test_percent_check=0.2,
@@ -135,7 +135,7 @@ class CurrentTestModel(LightningTestMixin, LightningTestModelBase):
 
     trainer_options = dict(
         show_progress_bar=False,
-        max_num_epochs=1,
+        max_epochs=1,
         train_percent_check=0.4,
         val_percent_check=0.2,
         test_percent_check=0.2,
@@ -209,7 +209,7 @@ def test_simple_cpu(tmpdir):
     # logger file to get meta
     trainer_options = dict(
         default_save_path=tmpdir,
-        max_num_epochs=1,
+        max_epochs=1,
         val_percent_check=0.1,
         train_percent_check=0.1,
     )
@@ -230,7 +230,7 @@ def test_cpu_model(tmpdir):
         default_save_path=tmpdir,
         show_progress_bar=False,
         logger=tutils.get_test_tube_logger(tmpdir),
-        max_num_epochs=1,
+        max_epochs=1,
         train_percent_check=0.4,
         val_percent_check=0.4
     )
@@ -253,7 +253,7 @@ def test_all_features_cpu_model(tmpdir):
         show_progress_bar=False,
         logger=tutils.get_test_tube_logger(tmpdir),
         accumulate_grad_batches=2,
-        max_num_epochs=1,
+        max_epochs=1,
         train_percent_check=0.4,
         val_percent_check=0.4
     )
@@ -314,7 +314,7 @@ def train_dataloader(self):
 
     trainer_options = dict(
         default_save_path=tmpdir,
-        max_num_epochs=1,
+        max_epochs=1,
         truncated_bptt_steps=truncated_bptt_steps,
         val_percent_check=0,
         weights_summary=None,
@@ -348,7 +348,7 @@ def test_single_gpu_model(tmpdir):
     trainer_options = dict(
         default_save_path=tmpdir,
         show_progress_bar=False,
-        max_num_epochs=1,
+        max_epochs=1,
         train_percent_check=0.1,
         val_percent_check=0.1,
         gpus=1