Merge pull request #7533 from toslunar/ptb-example-iter-reset

Implement `reset` method in the PTB example

examples/ptb/train_ptb.py

@@ -57,18 +57,22 @@ def forward(self, x):
 class ParallelSequentialIterator(chainer.dataset.Iterator):
 
     def __init__(self, dataset, batch_size, repeat=True):
+        super(ParallelSequentialIterator, self).__init__()
         self.dataset = dataset
         self.batch_size = batch_size  # batch size
+        self.repeat = repeat
+        length = len(dataset)
+        # Offsets maintain the position of each sequence in the mini-batch.
+        self.offsets = [i * length // batch_size for i in range(batch_size)]
+        self.reset()
+
+    def reset(self):
         # Number of completed sweeps over the dataset. In this case, it is
         # incremented if every word is visited at least once after the last
         # increment.
         self.epoch = 0
         # True if the epoch is incremented at the last iteration.
         self.is_new_epoch = False
-        self.repeat = repeat
-        length = len(dataset)
-        # Offsets maintain the position of each sequence in the mini-batch.
-        self.offsets = [i * length // batch_size for i in range(batch_size)]
         # NOTE: this is not a count of parameter updates. It is just a count of
         # calls of ``__next__``.
         self.iteration = 0