Files
baselines/baselines/common/models.py
Peter Zhokhov 217b111c88 merged refactor
2018-08-10 14:14:46 -07:00

178 lines
5.6 KiB
Python

import numpy as np
import tensorflow as tf
from baselines.a2c import utils
from baselines.a2c.utils import conv, fc, conv_to_fc, batch_to_seq, seq_to_batch
from baselines.common.mpi_running_mean_std import RunningMeanStd
import tensorflow.contrib.layers as layers
def nature_cnn(unscaled_images, **conv_kwargs):
"""
CNN from Nature paper.
"""
scaled_images = tf.cast(unscaled_images, tf.float32) / 255.
activ = tf.nn.relu
h = activ(conv(scaled_images, 'c1', nf=32, rf=8, stride=4, init_scale=np.sqrt(2),
**conv_kwargs))
h2 = activ(conv(h, 'c2', nf=64, rf=4, stride=2, init_scale=np.sqrt(2), **conv_kwargs))
h3 = activ(conv(h2, 'c3', nf=64, rf=3, stride=1, init_scale=np.sqrt(2), **conv_kwargs))
h3 = conv_to_fc(h3)
return activ(fc(h3, 'fc1', nh=512, init_scale=np.sqrt(2)))
def mlp(num_layers=2, num_hidden=64, activation=tf.tanh):
"""
Simple fully connected layer policy. Separate stacks of fully-connected layers are used for policy and value function estimation.
More customized fully-connected policies can be obtained by using PolicyWithV class directly.
Parameters:
----------
num_layers: int number of fully-connected layers (default: 2)
num_hidden: int size of fully-connected layers (default: 64)
activation: activation function (default: tf.tanh)
Returns:
-------
function that builds fully connected network with a given input placeholder
"""
def network_fn(X):
h = tf.layers.flatten(X)
for i in range(num_layers):
h = activation(fc(h, 'mlp_fc{}'.format(i), nh=num_hidden, init_scale=np.sqrt(2)))
return h, None
return network_fn
def cnn(**conv_kwargs):
def network_fn(X):
return nature_cnn(X, **conv_kwargs), None
return network_fn
def cnn_small(**conv_kwargs):
def network_fn(X):
h = tf.cast(X, tf.float32) / 255.
activ = tf.nn.relu
h = activ(conv(h, 'c1', nf=8, rf=8, stride=4, init_scale=np.sqrt(2), **conv_kwargs))
h = activ(conv(h, 'c2', nf=16, rf=4, stride=2, init_scale=np.sqrt(2), **conv_kwargs))
h = conv_to_fc(h)
h = activ(fc(h, 'fc1', nh=128, init_scale=np.sqrt(2)))
return h, None
return network_fn
def lstm(nlstm=128, layer_norm=False):
def network_fn(X, nenv=1):
nbatch = X.shape[0]
nsteps = nbatch // nenv
h = tf.layers.flatten(X)
M = tf.placeholder(tf.float32, [nbatch]) #mask (done t-1)
S = tf.placeholder(tf.float32, [nenv, 2*nlstm]) #states
xs = batch_to_seq(h, nenv, nsteps)
ms = batch_to_seq(M, nenv, nsteps)
if layer_norm:
h5, snew = utils.lnlstm(xs, ms, S, scope='lnlstm', nh=nlstm)
else:
h5, snew = utils.lstm(xs, ms, S, scope='lstm', nh=nlstm)
h = seq_to_batch(h5)
initial_state = np.zeros(S.shape.as_list(), dtype=float)
return h, {'S':S, 'M':M, 'state':snew, 'initial_state':initial_state}
return network_fn
def cnn_lstm(nlstm=128, layer_norm=False, **conv_kwargs):
def network_fn(X, nenv=1):
nbatch = X.shape[0]
nsteps = nbatch // nenv
h = nature_cnn(X, **conv_kwargs)
M = tf.placeholder(tf.float32, [nbatch]) #mask (done t-1)
S = tf.placeholder(tf.float32, [nenv, 2*nlstm]) #states
xs = batch_to_seq(h, nenv, nsteps)
ms = batch_to_seq(M, nenv, nsteps)
if layer_norm:
h5, snew = utils.lnlstm(xs, ms, S, scope='lnlstm', nh=nlstm)
else:
h5, snew = utils.lstm(xs, ms, S, scope='lstm', nh=nlstm)
h = seq_to_batch(h5)
initial_state = np.zeros(S.shape.as_list(), dtype=float)
return h, {'S':S, 'M':M, 'state':snew, 'initial_state':initial_state}
return network_fn
def cnn_lnlstm(nlstm=128, **conv_kwargs):
return cnn_lstm(nlstm, layer_norm=True, **conv_kwargs)
def conv_only(convs=[(32, 8, 4), (64, 4, 2), (64, 3, 1)], **conv_kwargs):
'''
convolutions-only net
Parameters:
----------
conv: list of triples (filter_number, filter_size, stride) specifying parameters for each layer.
Returns:
function that takes tensorflow tensor as input and returns the output of the last convolutional layer
'''
def network_fn(X):
out = X
with tf.variable_scope("convnet"):
for num_outputs, kernel_size, stride in convs:
out = layers.convolution2d(out,
num_outputs=num_outputs,
kernel_size=kernel_size,
stride=stride,
activation_fn=tf.nn.relu,
**conv_kwargs)
return out, None
return network_fn
def _normalize_clip_observation(x, clip_range=[-5.0, 5.0]):
rms = RunningMeanStd(shape=x.shape[1:])
norm_x = tf.clip_by_value((x - rms.mean) / rms.std, min(clip_range), max(clip_range))
return norm_x, rms
def get_network_builder(name):
# TODO: replace with reflection?
if name == 'cnn':
return cnn
elif name == 'cnn_small':
return cnn_small
elif name == 'conv_only':
return conv_only
elif name == 'mlp':
return mlp
elif name == 'lstm':
return lstm
elif name == 'cnn_lstm':
return cnn_lstm
elif name == 'cnn_lnlstm':
return cnn_lnlstm
else:
raise ValueError('Unknown network type: {}'.format(name))