pytorch/caffe2/python/hsm_util.py
Ahmed Taei 411059d649 Generate huffman tree
Summary:
In this diff :
[1] Change the output from generating all paths from root to labels to TreeProto.
TreeProto itself is required by inference and we can use hsm_util to get the
paths from TreeProto.

[2] Fix hsm_util index assigment.

Differential Revision: D4416731

fbshipit-source-id: 657d8b9b4df6fa30c9f92d391cf7e07b5c5db1f8
2017-01-19 16:14:23 -08:00

69 lines
2.3 KiB
Python

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals
from caffe2.proto import hsm_pb2
'''
Hierarchical softmax utility methods that can be used to:
1) create TreeProto structure given list of word_ids or NodeProtos
2) create HierarchyProto structure using the user-inputted TreeProto
'''
def create_node_with_words(words, name='node'):
node = hsm_pb2.NodeProto()
node.name = name
for word in words:
node.word_ids.append(word)
return node
def create_node_with_nodes(nodes, name='node'):
node = hsm_pb2.NodeProto()
node.name = name
for child_node in nodes:
new_child_node = node.children.add()
new_child_node.MergeFrom(child_node)
return node
def create_hierarchy(tree_proto):
max_index = 0
def create_path(path, word):
path_proto = hsm_pb2.PathProto()
path_proto.word_id = word
for entry in path:
new_path_node = path_proto.path_nodes.add()
new_path_node.index = entry[0]
new_path_node.length = entry[1]
new_path_node.target = entry[2]
return path_proto
def recursive_path_builder(node_proto, path, hierarchy_proto, max_index):
node_proto.offset = max_index
path.append([max_index,
len(node_proto.word_ids) + len(node_proto.children), 0])
max_index += len(node_proto.word_ids) + len(node_proto.children)
if hierarchy_proto.size < max_index:
hierarchy_proto.size = max_index
for target, node in enumerate(node_proto.children):
path[-1][2] = target
max_index = recursive_path_builder(node, path, hierarchy_proto,
max_index)
for target, word in enumerate(node_proto.word_ids):
path[-1][2] = target + len(node_proto.children)
path_entry = create_path(path, word)
new_path_entry = hierarchy_proto.paths.add()
new_path_entry.MergeFrom(path_entry)
del path[-1]
return max_index
node = tree_proto.root_node
hierarchy_proto = hsm_pb2.HierarchyProto()
path = []
max_index = recursive_path_builder(node, path, hierarchy_proto, max_index)
return hierarchy_proto