# Copyright 2016 The TensorFlow Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ==============================================================================
"""Extremely random forest graph builder. go/brain-tree."""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import math
import random

from tensorflow.contrib.tensor_forest.python import constants
from tensorflow.contrib.tensor_forest.python.ops import inference_ops
from tensorflow.contrib.tensor_forest.python.ops import training_ops

from tensorflow.python.framework import constant_op
from tensorflow.python.framework import dtypes
from tensorflow.python.framework import ops
from tensorflow.python.ops import array_ops
from tensorflow.python.ops import control_flow_ops
from tensorflow.python.ops import init_ops
from tensorflow.python.ops import math_ops
from tensorflow.python.ops import random_ops
from tensorflow.python.ops import state_ops
from tensorflow.python.ops import variable_scope
from tensorflow.python.ops import variables as tf_variables
from tensorflow.python.platform import tf_logging as logging


# A convenience class for holding random forest hyperparameters.
#
# To just get some good default parameters, use:
#   hparams = ForestHParams(num_classes=2, num_features=40).fill()
#
# Note that num_classes can not be inferred and so must always be specified.
# Also, either num_splits_to_consider or num_features should be set.
#
# To override specific values, pass them to the constructor:
#   hparams = ForestHParams(num_classes=5, num_trees=10, num_features=5).fill()
#
# TODO(thomaswc): Inherit from tf.HParams when that is publicly available.
class ForestHParams(object):
  """A base class for holding hyperparameters and calculating good defaults."""

  def __init__(self,
               num_trees=100,
               max_nodes=10000,
               bagging_fraction=1.0,
               num_splits_to_consider=0,
               feature_bagging_fraction=1.0,
               max_fertile_nodes=0,
               split_after_samples=250,