def preprocess(cls, gens):
if isinstance(gens, Basic):
gens = (gens, )
elif len(gens) == 1 and hasattr(gens[0], '__iter__'):
gens = gens[0]
if gens == (None, ):
gens = ()
elif has_dups(gens):
raise GeneratorsError("duplicated generators: %s" % str(gens))
elif any(gen.is_commutative is False for gen in gens):
raise GeneratorsError("non-commutative generators: %s" % str(gens))
return tuple(gens)
def __new__(cls, *partition):
"""
Generates a new partition object.
This method also verifies if the arguments passed are
valid and raises a ValueError if they are not.
Examples
========
>>> from diofant.combinatorics.partitions import Partition
>>> a = Partition([1, 2], [3])
>>> a
{{3}, {1, 2}}
>>> a.partition
[[1, 2], [3]]
>>> len(a)
2
>>> a.members
(1, 2, 3)
"""
args = partition
if not all(isinstance(part, (list, FiniteSet)) for part in args):
raise ValueError(
"Each argument to Partition should be a list or a FiniteSet")
# sort so we have a canonical reference for RGS
partition = sorted(sum(list(map(list, partition)), []),
key=default_sort_key)
if has_dups(partition):
raise ValueError("Partition contained duplicated elements.")
obj = FiniteSet.__new__(cls, *[FiniteSet(*x) for x in args])
obj.members = tuple(partition)
obj.size = len(partition)
return obj
def test_has_dups():
assert has_dups(set()) is False
assert has_dups(list(range(3))) is False
assert has_dups([1, 2, 1]) is True
def eval(cls, *args):
if all(isinstance(a, (int, Integer)) for a in args):
return eval_levicivita(*args)
if has_dups(args):
return S.Zero
def test_has_dups():
assert has_dups(set()) is False
assert has_dups(list(range(3))) is False
assert has_dups([1, 2, 1]) is True