def read(self, prev_interface_tuple, mem):
"""
returns the data read from memory.
:param prev_interface_tuple: Tuple [previous read, previous write, prev usage, prev links]
:param mem: the memory [batch_size, content_size, memory_size]
:return: the read data [batch_size, content_size]
"""
(wt, _, _, _) = prev_interface_tuple
memory = Memory(mem)
read_data = memory.attention_read(wt)
# flatten the data_gen in the last 2 dimensions
sz = read_data.size()[:-2]
return read_data.view(*sz, self.read_size)
def edit_memory(self, interface_tuple, update_data, mem):
"""
Edits the external memory and then returns it.
:param update_data: the parameters from the controllers [dictionary]
:param prev_interface_tuple: Tuple [previous read, previous write, prev usage, prev links]
:param mem: the memory [batch_size, content_size, memory_size]
:return: edited memory [batch_size, content_size, memory_size]
"""
(_, write_attention, _, _) = interface_tuple
# Write to memory
write_gate = update_data['write_gate']
add = update_data['write_vectors']
erase = update_data['erase_vectors']
if self.use_extra_write_gate:
add = add * write_gate
erase = erase * write_gate
memory = Memory(mem)
memory.erase_weighted(erase, write_attention)
memory.add_weighted(add, write_attention)
mem = memory.content
return mem
def update_write(self, update_data, prev_interface_tuple, mem):
"""
Updates the write attention switching between the NTM and DNC
mechanisms.
:param update_data: the parameters from the controllers [dictionary]
:param prev_interface_tuple: Tuple [previous read, previous write, prev usage, prev links]
:param prev_memory_BxMxA: the memory of the previous step (class)
:return: The new interface tuple with an updated usage and write attention
"""
(prev_read_attention, prev_write_attention, prev_usage,
prev_links) = prev_interface_tuple
# Obtain update parameters
key = update_data['write_content_keys']
strength = update_data['write_content_strengths']
gate = update_data['allocation_gate']
# retrieve memory Class
memory = Memory(mem)
free_gate = update_data['free_gate']
usage = self.mem_usage.calculate_usage(prev_write_attention, free_gate,
prev_read_attention, prev_usage)
# update the attention using either the NTM write mechanism (True) or
# the DNC (False)
if self.use_ntm_write:
# Parameters for shift addressing
shift = update_data['shifts']
sharp = update_data['sharpening']
write_attention = self.update_weight(prev_write_attention, memory,
strength, gate, key, shift,
sharp)
else:
write_gate = update_data['write_gate']
allocation_gate = gate
write_attention = self.update_write_weight(usage, memory,
allocation_gate,
write_gate, key,
strength)
interface_state_tuple = InterfaceStateTuple(prev_read_attention,
write_attention, usage,
prev_links)
return interface_state_tuple
def update_read(self, update_data, prev_interface_tuple, mem):
"""
Updates the read attention switching between the NTM and DNC
mechanisms.
:param update_data: the parameters from the controllers [dictionary]
:param prev_interface_tuple: Tuple [previous read, previous write, prev usage, prev links[
:param prev_memory_BxMxA: the memory of the previous step (class)
:return: The new interface tuple with an updated usage and write attention
"""
(prev_read_attention, prev_write_attention, prev_usage,
prev_links) = prev_interface_tuple
# Parameters for the content addressing
key = update_data['read_content_keys']
strength = update_data['read_content_strengths']
# retrieve memory Class
memory = Memory(mem)
# update the attention using either the NTM read mechanism (True) or
# the DNC (False)
if self.use_ntm_read:
# Parameters for shift addressing
shift = update_data['shifts_read']
sharp = update_data['sharpening_read']
gate = update_data['read_mode_shift']
read_attention = self.update_weight(prev_read_attention, memory,
strength, gate, key, shift,
sharp)
links = prev_links
else:
read_mode = update_data['read_mode']
links = self.temporal_linkage.calc_temporal_links(
prev_write_attention, prev_links)
read_attention = self.update_read_weight(links, memory,
prev_read_attention,
read_mode, key, strength)
interface_state_tuple = InterfaceStateTuple(read_attention,
prev_write_attention,
prev_usage, links)
return interface_state_tuple