def testD():
odds, evens = 0, 0
for p in itertools.permutations(range(6)):
a = list(p)
result = toCycles(a)
parity = cycle_parity(a)
print(a, result, cycle_parity(a))
if parity == 1:
evens += 1
elif parity == -1:
odds += 1
else:
assert False
assert evens == odds
def evaluate_point(T, W, d):
Q = sla.splu(T)
det = np.prod(Q.U.diagonal()) * cycle_parity(Q.perm_r) * cycle_parity(
Q.perm_c)
if np.abs(det) >= 1e-6:
X = Q.solve(W)
WW = T.dot(X)
assert np.allclose(WW, W)
F = d.T.dot(X)
D = det
N = F * D
return (D, N)
else:
return (None, None)
def testA():
a = [1, 0]
result = toCycles(a)
assert len(result) == 1
print(result)
assert cycle_parity(a) == -1
def testC():
a = [0, 2, 1]
result = toCycles(a)
assert len(result) == 2
print(result)
assert cycle_parity(a) == -1