add comments

python/paddle/v2/layer.py

@@ -53,20 +53,29 @@ import data_type
 __all__ = ['parse_network', 'data']
 
 
-def parse_network(*outputs, **kwargs):
+def parse_network(output_layers, extra_layers=None):
     """
-    Parse all output layers and then generate a ModelConfig object.
+    Parse all layers in the neural network graph and
+    then generate a ModelConfig object.
 
     ..  note::
 
         This function is used internally in paddle.v2 module. User should never
         invoke this method.
 
-    :param outputs: Output layers.
-    :type outputs: Layer
+    :param output_layers: Output layers.
+    :type output_layers: Layer
+    :param extra_layers: Some layers in the neural network graph are not in the
+                         path of output_layers.
+    :type extra_layers: Layer
     :return: A ModelConfig object instance.
     :rtype: ModelConfig
     """
+    if not isinstance(output_layers, collections.Sequence):
+        output_layers = [output_layers]
+    if extra_layers is not None and not isinstance(extra_layers,
+                                                   collections.Sequence):
+        extra_layers = [extra_layers]
 
     def __real_func__():
         """
@@ -74,8 +83,7 @@ def parse_network(*outputs, **kwargs):
         the plain old paddle configuration function.
         """
         context = dict()
-        real_output = [each.to_proto(context=context) for each in outputs]
-        extra_layers = kwargs.get('extra_layers', None)
+        real_output = [each.to_proto(context=context) for each in output_layers]
         if extra_layers is not None:
             extra_output = [
                 each.to_proto(context=context) for each in extra_layers

python/paddle/v2/tests/test_layer.py

@@ -59,13 +59,13 @@ class ImageLayerTest(unittest.TestCase):
                         num_channels=16,
                         pool_type=pooling.Max())
         maxout = layer.maxout(input=conv, num_channels=16, groups=4)
-        print layer.parse_network(maxpool, spp, maxout)
+        print layer.parse_network([maxpool, spp, maxout])
 
     def test_norm_layer(self):
         norm1 = layer.img_cmrnorm(input=conv, size=5)
         norm2 = layer.batch_norm(input=conv)
         norm3 = layer.sum_to_one_norm(input=conv)
-        print layer.parse_network(norm1, norm2, norm3)
+        print layer.parse_network([norm1, norm2, norm3])
 
 
 class AggregateLayerTest(unittest.TestCase):
@@ -78,7 +78,8 @@ class AggregateLayerTest(unittest.TestCase):
         first_seq = layer.first_seq(input=pixel)
         concat = layer.concat(input=[last_seq, first_seq])
         seq_concat = layer.seq_concat(a=last_seq, b=first_seq)
-        print layer.parse_network(pool, last_seq, first_seq, concat, seq_concat)
+        print layer.parse_network(
+            [pool, last_seq, first_seq, concat, seq_concat])
 
 
 class MathLayerTest(unittest.TestCase):
@@ -95,8 +96,10 @@ class MathLayerTest(unittest.TestCase):
         tensor = layer.tensor(a=pixel, b=pixel, size=1000)
         cos_sim = layer.cos_sim(a=pixel, b=pixel)
         trans = layer.trans(input=tensor)
-        print layer.parse_network(addto, linear_comb, interpolation, power,
-                                  scaling, slope, tensor, cos_sim, trans)
+        print layer.parse_network([
+            addto, linear_comb, interpolation, power, scaling, slope, tensor,
+            cos_sim, trans
+        ])
 
 
 class ReshapeLayerTest(unittest.TestCase):
@@ -110,7 +113,8 @@ class ReshapeLayerTest(unittest.TestCase):
         repeat = layer.repeat(input=pixel, num_repeats=4)
         reshape = layer.seq_reshape(input=pixel, reshape_size=4)
         rotate = layer.rotate(input=pixel, height=16, width=49)
-        print layer.parse_network(block_expand, expand, repeat, reshape, rotate)
+        print layer.parse_network(
+            [block_expand, expand, repeat, reshape, rotate])
 
 
 class RecurrentLayerTest(unittest.TestCase):
@@ -119,7 +123,7 @@ class RecurrentLayerTest(unittest.TestCase):
         recurrent = layer.recurrent(input=word)
         lstm = layer.lstmemory(input=word)
         gru = layer.grumemory(input=word)
-        print layer.parse_network(recurrent, lstm, gru)
+        print layer.parse_network([recurrent, lstm, gru])
 
 
 class CostLayerTest(unittest.TestCase):
@@ -139,10 +143,10 @@ class CostLayerTest(unittest.TestCase):
         cost10 = layer.sum_cost(input=inference)
         cost11 = layer.huber_cost(input=score, label=label)
 
-        print layer.parse_network(cost1, cost2)
-        print layer.parse_network(cost3, cost4)
-        print layer.parse_network(cost5, cost6)
-        print layer.parse_network(cost7, cost8, cost9, cost10, cost11)
+        print layer.parse_network([cost1, cost2])
+        print layer.parse_network([cost3, cost4])
+        print layer.parse_network([cost5, cost6])
+        print layer.parse_network([cost7, cost8, cost9, cost10, cost11])
 
         crf = layer.crf(input=inference, label=label)
         crf_decoding = layer.crf_decoding(input=inference, size=3)
@@ -151,8 +155,8 @@ class CostLayerTest(unittest.TestCase):
         nce = layer.nce(input=inference, label=label, num_classes=3)
         hsigmoid = layer.hsigmoid(input=inference, label=label, num_classes=3)
 
-        print layer.parse_network(crf, crf_decoding, ctc, warp_ctc, nce,
-                                  hsigmoid)
+        print layer.parse_network(
+            [crf, crf_decoding, ctc, warp_ctc, nce, hsigmoid])
 
 
 class OtherLayerTest(unittest.TestCase):
@@ -160,7 +164,7 @@ class OtherLayerTest(unittest.TestCase):
         maxid = layer.max_id(input=inference)
         sampling_id = layer.sampling_id(input=inference)
         eos = layer.eos(input=maxid, eos_id=5)
-        print layer.parse_network(maxid, sampling_id, eos)
+        print layer.parse_network([maxid, sampling_id, eos])
 
     def test_slicing_joining_layer(self):
         pad = layer.pad(input=conv, pad_c=[2, 3], pad_h=[1, 2], pad_w=[3, 1])

python/paddle/v2/topology.py

@@ -13,7 +13,6 @@
 # limitations under the License.
 
 import collections
-import copy
 
 from paddle.proto.ModelConfig_pb2 import ModelConfig
 
@@ -69,7 +68,7 @@ class Topology(object):
             extra_layers = __check__(extra_layers)
 
         self.__model_config__ = v2_layer.parse_network(
-            *layers, extra_layers=extra_layers)
+            layers, extra_layers=extra_layers)
 
         if extra_layers is not None:
             self.layers.extend(extra_layers)

python/paddle/v2/trainer.py

@@ -37,6 +37,9 @@ class SGD(object):
     :type cost: paddle.v2.config_base.Layer
     :param parameters: The parameters dictionary.
     :type parameters: paddle.v2.parameters.Parameters
+    :param extra_layers: Some layers in the neural network graph are not
+                         in the path of cost layer.
+    :type extra_layers: paddle.v2.config_base.Layer
     """
 
     def __init__(self, cost, parameters, update_equation, extra_layers=None):