in Experiments/PolicyNetworks.py [0:0]
def __init__(self, input_size, hidden_size, args, number_layers=4):
# Ensures inheriting from torch.nn.Module goes nicely and cleanly.
# super().__init__()
super(ContinuousLatentPolicyNetwork, self).__init__()
self.args = args
# Input size is actually input_size + number_subpolicies +1
self.input_size = input_size+self.args.z_dimensions+1
self.offset_for_z = input_size+1
self.hidden_size = hidden_size
# self.number_subpolicies = number_subpolicies
self.output_size = self.args.z_dimensions
self.num_layers = number_layers
self.b_exploration_bias = self.args.b_exploration_bias
self.batch_size = self.args.batch_size
# Define LSTM.
self.lstm = torch.nn.LSTM(input_size=self.input_size,hidden_size=self.hidden_size,num_layers=self.num_layers).to(device)
# Transform to output space - Latent z and Latent b.
# self.subpolicy_output_layer = torch.nn.Linear(self.hidden_size,self.output_size)
self.termination_output_layer = torch.nn.Linear(self.hidden_size,2)
# Sigmoid and Softmax activation functions for Bernoulli termination probability and latent z selection .
self.batch_softmax_layer = torch.nn.Softmax(dim=2)
self.batch_logsoftmax_layer = torch.nn.LogSoftmax(dim=2)
# Define output layers for the LSTM, and activations for this output layer.
self.mean_output_layer = torch.nn.Linear(self.hidden_size,self.output_size)
self.variances_output_layer = torch.nn.Linear(self.hidden_size, self.output_size)
self.activation_layer = torch.nn.Tanh()
self.variance_activation_layer = torch.nn.Softplus()
self.variance_activation_bias = 0.
self.variance_factor = 0.01
# # # Try initializing the network to something, so that we can escape the stupid constant output business.
for name, param in self.lstm.named_parameters():
if 'bias' in name:
torch.nn.init.constant_(param, 0.001)
elif 'weight' in name:
torch.nn.init.xavier_normal_(param,gain=5)
# Also initializing mean_output_layer to something large...
for name, param in self.mean_output_layer.named_parameters():
if 'bias' in name:
torch.nn.init.constant_(param, 0.)
elif 'weight' in name:
torch.nn.init.xavier_normal_(param,gain=2)