[keras] 创建桶装网络，以及创建全连接层

• K.layers.Dense(layer_size, activation='relu')：layer_size指的是输出的尺寸，如果是桶装网络的第一层那么就要指定输入尺寸input_dim =。

def cl_logits_subgraph(layer_sizes, input_size, num_classes, keep_prob=1.):
  """Construct multiple ReLU layers with dropout and a linear layer."""
  subgraph = K.models.Sequential(name='cl_logits')
  for i, layer_size in enumerate(layer_sizes):
    if i == 0:
      subgraph.add(
          K.layers.Dense(layer_size, activation='relu', input_dim=input_size))
    else:
      subgraph.add(K.layers.Dense(layer_size, activation='relu'))

    if keep_prob < 1.:
      subgraph.add(K.layers.Dropout(1. - keep_prob))
  subgraph.add(K.layers.Dense(1 if num_classes == 2 else num_classes))
  return subgraph