def test_base_image_member(self):
cf =Permutation.read_cycle_form
a = cf([[1, 2]],4)
b = cf([[1,2,3,4]], 4)
c = cf([[2,3]], 4)
e = cf([],4)
base, gens, c_gens, graphs = schreier_sims_algorithm_fixed_base([a,b],[1,2,3,4], e)
self.assertEqual(base_image_member(base,[1,3,2],graphs,e), c)
def prefix_postfix_image_member(self, pre, post, allow_base_change = False):
lookup = {ele:index for index, ele in enumerate(pre)}
image = []
for ele in self.base:
if ele in lookup:
image.append(post[lookup[ele]])
else:
if len(image) < len(pre):
raise NotImplementedError
#needs base change or new group.
else:
break
limit = len(image)
return schreier_sims_tools.base_image_member(self.base[:limit], image, self.schreier_graphs[:limit], self.identity)
def base_prefix_image_member(self, image):
limit = len(image)
return schreier_sims_tools.base_image_member(
self.base[:limit], image, self.schreier_graphs[:limit], self.identity
)
def base_image_member(self, image):
return schreier_sims_tools.base_image_member(self.base, image, self.schreier_graphs, self.identity)