def test():
assert binomial(7, 3) == 35
assert binomial(0, 0) == 1
assert binomial(1, 0) == 1
assert binomial(0, 1) == 0
assert binomial(
1543, 634
) == 127103521979248139661884595050302692072114625333816461647571438364482801578062268185939019831927710543644891679108093639691467979466411177318250931548804667267192030646116875003881007119966764992383016174407823444352165249728639847571592229832113238415348489512831060701471487834812550521403788703534654431344329462541634971732197170414906629071055802381322184009159362499960475076746698583466181504060523973736761406471112019069930703149760846502951040
def index(self, perm):
'''Get the index number of permutation `perm` in this space.'''
if not isinstance(perm, collections.abc.Iterable):
raise ValueError
perm = sequence_tools.ensure_iterable_is_immutable_sequence(perm)
perm_set = set(perm) if not isinstance(perm, UnrecurrentedPerm) \
else set(perm._perm_sequence)
if not (perm_set <= set(self.sequence)):
raise ValueError
if sequence_tools.get_length(perm) != self.n_elements:
raise ValueError
if not isinstance(perm, self.perm_type):
perm = self.perm_type(perm, self)
if self.sequence != perm.nominal_perm_space.sequence:
# (This also covers `self.rapplied != perm.rapplied`)
raise ValueError
if self.domain != perm.domain:
# (This also covers `self.dapplied != perm.dapplied`)
raise ValueError
if self.is_degreed and (perm.degree not in self.degrees):
raise ValueError
# At this point we know the permutation contains the correct items, and
# has the correct degree.
if perm.is_dapplied:
return self.undapplied.index(perm.undapplied)
#######################################################################
elif self.is_degreed:
if perm.is_rapplied: return self.unrapplied.index(perm.unrapplied)
wip_perm_number = 0
wip_perm_sequence_dict = dict(self.fixed_map)
unused_values = list(self.free_values)
for i, value in enumerate(perm._perm_sequence):
if i in self.fixed_indices:
continue
unused_values.remove(value)
lower_values = [j for j in unused_values if j < value]
for lower_value in lower_values:
temp_fixed_map = dict(wip_perm_sequence_dict)
temp_fixed_map[i] = lower_value
wip_perm_number += PermSpace(
self.sequence_length,
degrees=self.degrees,
fixed_map=temp_fixed_map).length
wip_perm_sequence_dict[self.domain[i]] = value
perm_number = wip_perm_number
#######################################################################
elif self.is_recurrent:
assert not self.is_degreed and not self.is_dapplied
wip_perm_number = 0
unused_values = list(self.sequence)
reserved_values = list(self.fixed_map.values())
perm_sequence_list = list(perm._perm_sequence)
shit_set = set()
for i, value in enumerate(perm._perm_sequence):
if i in self.fixed_map:
if self.fixed_map[i] == value:
unused_values.remove(value)
reserved_values.remove(value)
continue
else:
raise ValueError
lower_values = [
thing
for thing in nifty_collections.OrderedSet(unused_values)
if (thing not in reserved_values or unused_values.count(
thing) > reserved_values.count(thing))
and unused_values.index(thing) < unused_values.index(value)
and thing not in shit_set
]
unused_values.remove(value)
for lower_value in lower_values:
temp_fixed_map = dict(
enumerate(perm_sequence_list[:i] + [lower_value]))
temp_fixed_map.update(self.fixed_map)
candidate_sub_perm_space = \
PermSpace._create_with_cut_prefix(
self.sequence,
n_elements=self.n_elements,
fixed_map=temp_fixed_map,
is_combination=self.is_combination,
shit_set=shit_set, perm_type=self.perm_type
)
wip_perm_number += candidate_sub_perm_space.length
if self.is_combination:
shit_set.add(lower_value)
perm_number = wip_perm_number
#######################################################################
elif self.is_fixed:
assert not self.is_degreed and not self.is_recurrent
free_values_perm_sequence = []
for i, perm_item in zip(self.domain, perm._perm_sequence):
if i in self.fixed_map:
if self.fixed_map[i] != perm_item:
raise ValueError
else:
free_values_perm_sequence.append(perm_item)
# At this point we know all the items that should be fixed are
# fixed.
perm_number = self._free_values_unsliced_perm_space.index(
free_values_perm_sequence)
#######################################################################
elif self.is_combination:
if perm.is_rapplied:
return self.unrapplied.index(perm.unrapplied)
assert not self.is_rapplied and not self.is_recurrent and \
not self.is_dapplied and not self.is_fixed and \
not self.is_degreed
if not cute_iter_tools.is_sorted(perm._perm_sequence):
raise ValueError
processed_perm_sequence = tuple(
self.sequence_length - 1 - item
for item in perm._perm_sequence[::-1])
perm_number = self.unsliced.length - 1 - sum(
(math_tools.binomial(item, i)
for i, item in enumerate(processed_perm_sequence, start=1)),
0)
#######################################################################
else:
factoradic_number = []
unused_values = list(self.sequence)
for i, value in enumerate(perm._perm_sequence):
index_of_current_number = unused_values.index(value)
factoradic_number.append(index_of_current_number)
unused_values.remove(value)
perm_number = math_tools.from_factoradic(
factoradic_number +
[0] * self.n_unused_elements) // math.factorial(
self.n_unused_elements)
#######################################################################
if perm_number not in self.canonical_slice:
raise ValueError
return perm_number - self.canonical_slice.start
def __getitem__(self, i):
if isinstance(i, (slice, sequence_tools.CanonicalSlice)):
canonical_slice = sequence_tools.CanonicalSlice(
i, self.length, offset=self.canonical_slice.start)
return PermSpace(self.sequence,
domain=self.domain,
n_elements=self.n_elements,
fixed_map=self.fixed_map,
degrees=self.degrees,
is_combination=self.is_combination,
slice_=canonical_slice,
perm_type=self.perm_type)
assert isinstance(i, numbers.Integral)
if i <= -1:
i += self.length
if not (0 <= i < self.length):
raise IndexError
elif self.is_sliced:
return self.unsliced[i + self.canonical_slice.start]
elif self.is_dapplied:
return self.perm_type(self.undapplied[i], perm_space=self)
#######################################################################
elif self.is_degreed:
if self.is_rapplied:
assert not self.is_recurrent and \
not self.is_partial and not self.is_combination and \
not self.is_dapplied and not self.is_sliced
return self.perm_type(map(self.sequence.__getitem__,
self.unrapplied[i]),
perm_space=self)
assert not self.is_rapplied and not self.is_recurrent and \
not self.is_partial and not self.is_combination and \
not self.is_dapplied and not self.is_sliced
# If that wasn't an example of asserting one's dominance, I don't
# know what is.
available_values = list(self.free_values)
wip_perm_sequence_dict = dict(self.fixed_map)
wip_n_cycles_in_fixed_items = \
self._n_cycles_in_fixed_items_of_just_fixed
wip_i = i
for j in self.sequence:
if j in wip_perm_sequence_dict:
continue
for unused_value in available_values:
candidate_perm_sequence_dict = dict(wip_perm_sequence_dict)
candidate_perm_sequence_dict[j] = unused_value
### Checking whether we closed a cycle: ###################
# #
if j == unused_value:
closed_cycle = True
else:
current = j
while True:
current = candidate_perm_sequence_dict[current]
if current == j:
closed_cycle = True
break
elif current not in candidate_perm_sequence_dict:
closed_cycle = False
break
# #
### Finished checking whether we closed a cycle. ##########
candidate_n_cycles_in_fixed_items = \
wip_n_cycles_in_fixed_items + closed_cycle
candidate_fixed_perm_space_length = sum(
math_tools.abs_stirling(
self.sequence_length -
len(candidate_perm_sequence_dict),
self.sequence_length - degree -
candidate_n_cycles_in_fixed_items)
for degree in self.degrees)
if wip_i < candidate_fixed_perm_space_length:
available_values.remove(unused_value)
wip_perm_sequence_dict[j] = unused_value
wip_n_cycles_in_fixed_items = \
candidate_n_cycles_in_fixed_items
break
wip_i -= candidate_fixed_perm_space_length
else:
raise RuntimeError
assert wip_i == 0
return self.perm_type(
(wip_perm_sequence_dict[k] for k in self.domain), self)
#######################################################################
elif self.is_recurrent:
assert not self.is_dapplied and not self.is_degreed and \
not self.is_sliced
available_values = list(self.sequence)
reserved_values = nifty_collections.Bag(self.fixed_map.values())
wip_perm_sequence_dict = dict(self.fixed_map)
wip_i = i
shit_set = set()
for j in range(self.n_elements):
if j in self.fixed_map:
available_values.remove(self.fixed_map[j])
reserved_values[self.fixed_map[j]] -= 1
continue
unused_values = [
item for item in
nifty_collections.OrderedBag(available_values) -
reserved_values if item not in shit_set
]
for unused_value in unused_values:
wip_perm_sequence_dict[j] = unused_value
candidate_sub_perm_space = \
PermSpace._create_with_cut_prefix(
self.sequence,
n_elements=self.n_elements,
fixed_map=wip_perm_sequence_dict,
is_combination=self.is_combination,
shit_set=shit_set, perm_type=self.perm_type
)
if wip_i < candidate_sub_perm_space.length:
available_values.remove(unused_value)
break
else:
wip_i -= candidate_sub_perm_space.length
if self.is_combination:
shit_set.add(wip_perm_sequence_dict[j])
del wip_perm_sequence_dict[j]
else:
raise RuntimeError
assert wip_i == 0
return self.perm_type(
dict_tools.get_tuple(wip_perm_sequence_dict, self.domain),
self)
#######################################################################
elif self.is_fixed:
free_values_perm = self._free_values_unsliced_perm_space[i]
free_values_perm_iterator = iter(free_values_perm)
return self.perm_type(
tuple((self._undapplied_fixed_map[m] if (
m in self.fixed_indices
) else next(free_values_perm_iterator))
for m in self.indices), self)
#######################################################################
elif self.is_combination:
wip_number = self.length - 1 - i
wip_perm_sequence = []
for i in range(self.n_elements, 0, -1):
for j in range(self.sequence_length, i - 2, -1):
candidate = math_tools.binomial(j, i)
if candidate <= wip_number:
wip_perm_sequence.append(self.sequence[-(j + 1)])
wip_number -= candidate
break
else:
raise RuntimeError
result = tuple(wip_perm_sequence)
assert len(result) == self.n_elements
return self.perm_type(result, self)
#######################################################################
else:
factoradic_number = math_tools.to_factoradic(
i * math.factorial(self.n_unused_elements),
n_digits_pad=self.sequence_length)
if self.is_partial:
factoradic_number = factoradic_number[:-self.n_unused_elements]
unused_numbers = list(self.sequence)
result = tuple(
unused_numbers.pop(factoradic_digit)
for factoradic_digit in factoradic_number)
assert sequence_tools.get_length(result) == self.n_elements
return self.perm_type(result, self)
def test():
assert binomial(7, 3) == 35
assert binomial(0, 0) == 1
assert binomial(1, 0) == 1
assert binomial(0, 1) == 0
assert binomial(1543, 634) == 127103521979248139661884595050302692072114625333816461647571438364482801578062268185939019831927710543644891679108093639691467979466411177318250931548804667267192030646116875003881007119966764992383016174407823444352165249728639847571592229832113238415348489512831060701471487834812550521403788703534654431344329462541634971732197170414906629071055802381322184009159362499960475076746698583466181504060523973736761406471112019069930703149760846502951040
def index(self, perm):
'''Get the index number of permutation `perm` in this space.'''
if not isinstance(perm, collections.Iterable):
raise ValueError
try:
perm = sequence_tools.ensure_iterable_is_immutable_sequence(
perm,
allow_unordered=False
)
except sequence_tools.UnorderedIterableException:
raise ValueError('An unordered iterable is never contained in a '
'`PermSpace`. Try an ordered one.')
perm_set = set(perm) if not isinstance(perm, UnrecurrentedPerm) \
else set(perm._perm_sequence)
if not (perm_set <= set(self.sequence)):
raise ValueError
if sequence_tools.get_length(perm) != self.n_elements:
raise ValueError
if not isinstance(perm, self.perm_type):
perm = self.perm_type(perm, self)
if self.sequence != perm.nominal_perm_space.sequence:
# (This also covers `self.rapplied != perm.rapplied`)
raise ValueError
if self.domain != perm.domain:
# (This also covers `self.dapplied != perm.dapplied`)
raise ValueError
if self.is_degreed and (perm.degree not in self.degrees):
raise ValueError
# At this point we know the permutation contains the correct items, and
# has the correct degree.
if perm.is_dapplied: return self.undapplied.index(perm.undapplied)
#######################################################################
elif self.is_degreed:
if perm.is_rapplied: return self.unrapplied.index(perm.unrapplied)
wip_perm_number = 0
wip_perm_sequence_dict = dict(self.fixed_map)
unused_values = list(self.free_values)
for i, value in enumerate(perm._perm_sequence):
if i in self.fixed_indices:
continue
unused_values.remove(value)
lower_values = [j for j in unused_values if j < value]
for lower_value in lower_values:
temp_fixed_map = dict(wip_perm_sequence_dict)
temp_fixed_map[i] = lower_value
wip_perm_number += PermSpace(
self.sequence_length, degrees=self.degrees,
fixed_map=temp_fixed_map
).length
wip_perm_sequence_dict[self.domain[i]] = value
perm_number = wip_perm_number
#######################################################################
elif self.is_recurrent:
assert not self.is_degreed and not self.is_dapplied
wip_perm_number = 0
unused_values = list(self.sequence)
reserved_values = list(self.fixed_map.values())
perm_sequence_list = list(perm._perm_sequence)
shit_set = set()
for i, value in enumerate(perm._perm_sequence):
if i in self.fixed_map:
if self.fixed_map[i] == value:
unused_values.remove(value)
reserved_values.remove(value)
continue
else:
raise ValueError
lower_values = [
thing for thing in
nifty_collections.OrderedSet(unused_values) if
(thing not in reserved_values or unused_values.count(thing)
> reserved_values.count(thing)) and
unused_values.index(thing) < unused_values.index(value) and
thing not in shit_set
]
unused_values.remove(value)
for lower_value in lower_values:
temp_fixed_map = dict(
enumerate(perm_sequence_list[:i] + [lower_value])
)
temp_fixed_map.update(self.fixed_map)
candidate_sub_perm_space = \
PermSpace._create_with_cut_prefix(
self.sequence,
n_elements=self.n_elements,
fixed_map=temp_fixed_map,
is_combination=self.is_combination,
shit_set=shit_set, perm_type=self.perm_type
)
wip_perm_number += candidate_sub_perm_space.length
if self.is_combination:
shit_set.add(lower_value)
perm_number = wip_perm_number
#######################################################################
elif self.is_fixed:
assert not self.is_degreed and not self.is_recurrent
free_values_perm_sequence = []
for i, perm_item in zip(self.domain, perm._perm_sequence):
if i in self.fixed_map:
if self.fixed_map[i] != perm_item:
raise ValueError
else:
free_values_perm_sequence.append(perm_item)
# At this point we know all the items that should be fixed are
# fixed.
perm_number = self._free_values_unsliced_perm_space.index(
free_values_perm_sequence
)
#######################################################################
elif self.is_combination:
if perm.is_rapplied:
return self.unrapplied.index(perm.unrapplied)
assert not self.is_rapplied and not self.is_recurrent and \
not self.is_dapplied and not self.is_fixed and \
not self.is_degreed
if not cute_iter_tools.is_sorted(perm._perm_sequence):
raise ValueError
processed_perm_sequence = tuple(
self.sequence_length - 1 -
item for item in perm._perm_sequence[::-1]
)
perm_number = self.unsliced.length - 1 - sum(
(math_tools.binomial(item, i) for i, item in
enumerate(processed_perm_sequence, start=1)),
0
)
#######################################################################
else:
factoradic_number = []
unused_values = list(self.sequence)
for i, value in enumerate(perm._perm_sequence):
index_of_current_number = unused_values.index(value)
factoradic_number.append(index_of_current_number)
unused_values.remove(value)
perm_number = math_tools.from_factoradic(
factoradic_number +
[0] * self.n_unused_elements
) // math.factorial(self.n_unused_elements)
#######################################################################
if perm_number not in self.canonical_slice:
raise ValueError
return perm_number - self.canonical_slice.start
def __getitem__(self, i):
if isinstance(i, (slice, sequence_tools.CanonicalSlice)):
canonical_slice = sequence_tools.CanonicalSlice(
i, self.length, offset=self.canonical_slice.start
)
return PermSpace(
self.sequence, domain=self.domain, n_elements=self.n_elements,
fixed_map=self.fixed_map, degrees=self.degrees,
is_combination=self.is_combination, slice_=canonical_slice,
perm_type=self.perm_type
)
assert isinstance(i, numbers.Integral)
if i <= -1:
i += self.length
if not (0 <= i < self.length):
raise IndexError
elif self.is_sliced:
return self.unsliced[i + self.canonical_slice.start]
elif self.is_dapplied:
return self.perm_type(self.undapplied[i], perm_space=self)
#######################################################################
elif self.is_degreed:
if self.is_rapplied:
assert not self.is_recurrent and \
not self.is_partial and not self.is_combination and \
not self.is_dapplied and not self.is_sliced
return self.perm_type(map(self.sequence.__getitem__,
self.unrapplied[i]),
perm_space=self)
assert not self.is_rapplied and not self.is_recurrent and \
not self.is_partial and not self.is_combination and \
not self.is_dapplied and not self.is_sliced
# If that wasn't an example of asserting one's dominance, I don't
# know what is.
available_values = list(self.free_values)
wip_perm_sequence_dict = dict(self.fixed_map)
wip_n_cycles_in_fixed_items = \
self._n_cycles_in_fixed_items_of_just_fixed
wip_i = i
for j in self.sequence:
if j in wip_perm_sequence_dict:
continue
for unused_value in available_values:
candidate_perm_sequence_dict = dict(wip_perm_sequence_dict)
candidate_perm_sequence_dict[j] = unused_value
### Checking whether we closed a cycle: ###################
# #
if j == unused_value:
closed_cycle = True
else:
current = j
while True:
current = candidate_perm_sequence_dict[current]
if current == j:
closed_cycle = True
break
elif current not in candidate_perm_sequence_dict:
closed_cycle = False
break
# #
### Finished checking whether we closed a cycle. ##########
candidate_n_cycles_in_fixed_items = \
wip_n_cycles_in_fixed_items + closed_cycle
candidate_fixed_perm_space_length = sum(
math_tools.abs_stirling(
self.sequence_length -
len(candidate_perm_sequence_dict),
self.sequence_length - degree -
candidate_n_cycles_in_fixed_items
) for degree in self.degrees
)
if wip_i < candidate_fixed_perm_space_length:
available_values.remove(unused_value)
wip_perm_sequence_dict[j] = unused_value
wip_n_cycles_in_fixed_items = \
candidate_n_cycles_in_fixed_items
break
wip_i -= candidate_fixed_perm_space_length
else:
raise RuntimeError
assert wip_i == 0
return self.perm_type((wip_perm_sequence_dict[k] for k in
self.domain), self)
#######################################################################
elif self.is_recurrent:
assert not self.is_dapplied and not self.is_degreed and \
not self.is_sliced
available_values = list(self.sequence)
reserved_values = nifty_collections.Bag(self.fixed_map.values())
wip_perm_sequence_dict = dict(self.fixed_map)
wip_i = i
shit_set = set()
for j in range(self.n_elements):
if j in self.fixed_map:
available_values.remove(self.fixed_map[j])
reserved_values[self.fixed_map[j]] -= 1
continue
unused_values = [
item for item in
nifty_collections.OrderedBag(available_values) -
reserved_values if item not in shit_set
]
for unused_value in unused_values:
wip_perm_sequence_dict[j] = unused_value
candidate_sub_perm_space = \
PermSpace._create_with_cut_prefix(
self.sequence,
n_elements=self.n_elements,
fixed_map=wip_perm_sequence_dict,
is_combination=self.is_combination,
shit_set=shit_set, perm_type=self.perm_type
)
if wip_i < candidate_sub_perm_space.length:
available_values.remove(unused_value)
break
else:
wip_i -= candidate_sub_perm_space.length
if self.is_combination:
shit_set.add(wip_perm_sequence_dict[j])
del wip_perm_sequence_dict[j]
else:
raise RuntimeError
assert wip_i == 0
return self.perm_type(
dict_tools.get_tuple(wip_perm_sequence_dict, self.domain),
self
)
#######################################################################
elif self.is_fixed:
free_values_perm = self._free_values_unsliced_perm_space[i]
free_values_perm_iterator = iter(free_values_perm)
return self.perm_type(
tuple(
(self._undapplied_fixed_map[m] if
(m in self.fixed_indices) else
next(free_values_perm_iterator))
for m in range(self.sequence_length)
),
self
)
#######################################################################
elif self.is_combination:
wip_number = self.length - 1 - i
wip_perm_sequence = []
for i in range(self.n_elements, 0, -1):
for j in range(self.sequence_length, i - 2, -1):
candidate = math_tools.binomial(j, i)
if candidate <= wip_number:
wip_perm_sequence.append(
self.sequence[-(j+1)]
)
wip_number -= candidate
break
else:
raise RuntimeError
result = tuple(wip_perm_sequence)
assert len(result) == self.n_elements
return self.perm_type(result, self)
#######################################################################
else:
factoradic_number = math_tools.to_factoradic(
i * math.factorial(
self.n_unused_elements),
n_digits_pad=self.sequence_length
)
if self.is_partial:
factoradic_number = factoradic_number[:-self.n_unused_elements]
unused_numbers = list(self.sequence)
result = tuple(unused_numbers.pop(factoradic_digit) for
factoradic_digit in factoradic_number)
assert sequence_tools.get_length(result) == self.n_elements
return self.perm_type(result, self)
