Add docstrings for batchers

spacy/gold/batchers.py

@@ -19,6 +19,22 @@ def configure_minibatch_by_padded_size(
     discard_oversize: bool,
     get_length: Optional[Callable[[ItemT], int]] = None
 ) -> BatcherT:
+    """Create a batcher that uses the `batch_by_padded_size` strategy.
+    
+    The padded size is defined as the maximum length of sequences within the
+    batch multiplied by the number of sequences in the batch.
+
+    size (int or Iterable[int]): The largest padded size to batch sequences into.
+        Can be a single integer, or a sequence, allowing for variable batch sizes.
+    buffer (int): The number of sequences to accumulate before sorting by length.
+        A larger buffer will result in more even sizing, but if the buffer is
+        very large, the iteration order will be less random, which can result
+        in suboptimal training.
+    discard_oversize (bool): Whether to discard sequences that are by themselves
+        longer than the largest padded batch size.
+    get_length (Callable or None): Function to get the length of a sequence item.
+        The `len` function is used by default.
+    """
     # Avoid displacing optional values from the underlying function.
     optionals = {"get_length": get_length} if get_length is not None else {}
     return partial(
@@ -38,6 +54,16 @@ def configure_minibatch_by_words(
     discard_oversize: bool,
     get_length: Optional[Callable[[ItemT], int]] = None
 ) -> BatcherT:
+    """Create a batcher that uses the "minibatch by words" strategy.
+
+    size (int or Iterable[int]): The target number of words per batch.
+        Can be a single integer, or a sequence, allowing for variable batch sizes.
+    tolerance (float): What percentage of the size to allow batches to exceed.
+    discard_oversize (bool): Whether to discard sequences that by themselves
+        exceed the tolerated size.
+    get_length (Callable or None): Function to get the length of a sequence
+        item. The `len` function is used by default.
+    """
     optionals = {"get_length": get_length} if get_length is not None else {}
     return partial(
         minibatch_by_words, size=size, discard_oversize=discard_oversize, **optionals
@@ -48,22 +74,43 @@ def configure_minibatch_by_words(
 def configure_minibatch(
     size: Sizing, get_length: Optional[Callable[[ItemT], int]] = None
 ) -> BatcherT:
+    """Create a batcher that creates batches of the specified size.
+
+    size (int or Iterable[int]): The target number of items per batch.
+        Can be a single integer, or a sequence, allowing for variable batch sizes.
+    """
     optionals = {"get_length": get_length} if get_length is not None else {}
     return partial(minibatch, size=size, **optionals)
 
 
 def minibatch_by_padded_size(
-    docs: Iterator["Doc"],
+    seqs: Iterable[ItemT],
     size: Sizing,
     buffer: int = 256,
     discard_oversize: bool = False,
     get_length: Callable = len,
-) -> Iterator[Iterator["Doc"]]:
+) -> Iterable[List[ItemT]]:
+    """Minibatch a sequence by the size of padded batches that would result,
+    with sequences binned by length within a window.
+    
+    The padded size is defined as the maximum length of sequences within the
+    batch multiplied by the number of sequences in the batch.
+
+    size (int): The largest padded size to batch sequences into.
+    buffer (int): The number of sequences to accumulate before sorting by length.
+        A larger buffer will result in more even sizing, but if the buffer is
+        very large, the iteration order will be less random, which can result
+        in suboptimal training.
+    discard_oversize (bool): Whether to discard sequences that are by themselves
+        longer than the largest padded batch size.
+    get_length (Callable or None): Function to get the length of a sequence item.
+        The `len` function is used by default.
+    """
     if isinstance(size, int):
         size_ = itertools.repeat(size)
     else:
         size_ = size
-    for outer_batch in minibatch(docs, size=buffer):
+    for outer_batch in minibatch(seqs, size=buffer):
         outer_batch = list(outer_batch)
         target_size = next(size_)
         for indices in _batch_by_length(outer_batch, target_size, get_length):
@@ -76,12 +123,20 @@ def minibatch_by_padded_size(
 
 
 def minibatch_by_words(
-    docs, size, tolerance=0.2, discard_oversize=False, get_length=len
+    seqs: Iterable[ItemT], size: Sizing, tolerance=0.2, discard_oversize=False, get_length=len
-):
+) -> Iterable[List[ItemT]]:
     """Create minibatches of roughly a given number of words. If any examples
     are longer than the specified batch length, they will appear in a batch by
     themselves, or be discarded if discard_oversize=True.
-    The argument 'docs' can be a list of strings, Docs or Examples.
+
+    seqs (Iterable[Sequence]): The sequences to minibatch.
+    size (int or Iterable[int]): The target number of words per batch.
+        Can be a single integer, or a sequence, allowing for variable batch sizes.
+    tolerance (float): What percentage of the size to allow batches to exceed.
+    discard_oversize (bool): Whether to discard sequences that by themselves
+        exceed the tolerated size.
+    get_length (Callable or None): Function to get the length of a sequence
+        item. The `len` function is used by default.
     """
     if isinstance(size, int):
         size_ = itertools.repeat(size)
@@ -95,20 +150,20 @@ def minibatch_by_words(
     overflow = []
     batch_size = 0
     overflow_size = 0
-    for doc in docs:
+    for seq in seqs:
-        n_words = get_length(doc)
+        n_words = get_length(seq)
         # if the current example exceeds the maximum batch size, it is returned separately
         # but only if discard_oversize=False.
         if n_words > target_size + tol_size:
             if not discard_oversize:
-                yield [doc]
+                yield [seq]
         # add the example to the current batch if there's no overflow yet and it still fits
         elif overflow_size == 0 and (batch_size + n_words) <= target_size:
-            batch.append(doc)
+            batch.append(seq)
             batch_size += n_words
         # add the example to the overflow buffer if it fits in the tolerance margin
         elif (batch_size + overflow_size + n_words) <= (target_size + tol_size):
-            overflow.append(doc)
+            overflow.append(seq)
             overflow_size += n_words
         # yield the previous batch and start a new one. The new one gets the overflow examples.
         else:
@@ -122,11 +177,11 @@ def minibatch_by_words(
             overflow_size = 0
             # this example still fits
             if (batch_size + n_words) <= target_size:
-                batch.append(doc)
+                batch.append(seq)
                 batch_size += n_words
             # this example fits in overflow
             elif (batch_size + n_words) <= (target_size + tol_size):
-                overflow.append(doc)
+                overflow.append(seq)
                 overflow_size += n_words
             # this example does not fit with the previous overflow: start another new batch
             else:
@@ -134,7 +189,7 @@ def minibatch_by_words(
                     yield batch
                 target_size = next(size_)
                 tol_size = target_size * tolerance
-                batch = [doc]
+                batch = [seq]
                 batch_size = n_words
     batch.extend(overflow)
     if batch: