def move_pieces(self):
"""
Move pieces to new action F instances to make it fit, if needed.
@return: Created action F instances.
@rtype: C{list} of L{ActionF}
@note: Function may change L{pieces}.
"""
global townname_serial
if len(self.pieces) <= 255:
return [] # Trivially correct.
# There are too many pieces.
number_action_f = (len(self.pieces) + 254) // 255
pow2 = 1
while pow2 < number_action_f:
pow2 = pow2 * 2
if pow2 < 255: number_action_f = pow2
heap = [] # Heap of (summed probability, subset-of-pieces)
i = 0
while i < number_action_f:
# Index 'i' is added to have a unique sorting when lists have equal total probabilities.
heapq.heappush(heap, (0, i, []))
i = i + 1
finished_actions = []
# Index 'idx' is added to have a unique sorting when pieces have equal probabilities.
rev_pieces = sorted(((p.probability.value, idx, p)
for idx, p in enumerate(self.pieces)),
reverse=True)
for prob, _idx, piece in rev_pieces:
while True:
sub = heapq.heappop(heap)
if len(sub[2]) < 255:
break
# If a subset already has the max number of parts, consider it finished.
finished_actions.append(sub)
sub[2].append(piece)
sub = (sub[0] + prob, sub[1], sub[2])
heapq.heappush(heap, sub)
finished_actions.extend(heap)
# To ensure the chances do not get messed up due to one part needing less bits for its
# selection, all parts are forced to use the same number of bits.
max_prob = max(sub[0] for sub in finished_actions)
num_bits = 1
while (1 << num_bits) < max_prob:
num_bits = num_bits + 1
# Assign to action F
actFs = []
for _prob, _idx, sub in finished_actions:
actF_name = expression.Identifier(
"**townname #{:d}**".format(townname_serial), None)
townname_serial = townname_serial + 1
town_part = TownNamesPart(sub, self.pos)
town_part.set_numbits(num_bits)
actF = actionF.ActionF(actF_name, None, None, [town_part],
self.pos)
actFs.append(actF)
# Remove pieces of 'sub' from self.pieces
counts = len(self.pieces), len(sub)
sub_set = set(sub)
self.pieces = [
piece for piece in self.pieces if piece not in sub_set
]
assert len(self.pieces) == counts[0] - counts[1]
self.pieces.append(
TownNamesEntryDefinition(actF_name,
expression.ConstantNumeric(1),
self.pos))
# update self.parts
return actFs
def get_action_list(self):
return self.actFs + [
actionF.ActionF(self.name, self.id_number, self.style_name,
self.parts, self.pos)
]