RosettaCodeData/Task/Faces-from-a-mesh/Python/faces-from-a-mesh.py

51 lines
1.6 KiB
Python

def perim_equal(p1, p2):
# Cheap tests first
if len(p1) != len(p2) or set(p1) != set(p2):
return False
if any(p2 == (p1[n:] + p1[:n]) for n in range(len(p1))):
return True
p2 = p2[::-1] # not inplace
return any(p2 == (p1[n:] + p1[:n]) for n in range(len(p1)))
def edge_to_periphery(e):
edges = sorted(e)
p = list(edges.pop(0)) if edges else []
last = p[-1] if p else None
while edges:
for n, (i, j) in enumerate(edges):
if i == last:
p.append(j)
last = j
edges.pop(n)
break
elif j == last:
p.append(i)
last = i
edges.pop(n)
break
else:
#raise ValueError(f'Invalid edge format: {e}')
return ">>>Error! Invalid edge format<<<"
return p[:-1]
if __name__ == '__main__':
print('Perimeter format equality checks:')
for eq_check in [
{ 'Q': (8, 1, 3),
'R': (1, 3, 8)},
{ 'U': (18, 8, 14, 10, 12, 17, 19),
'V': (8, 14, 10, 12, 17, 19, 18)} ]:
(n1, p1), (n2, p2) = eq_check.items()
eq = '==' if perim_equal(p1, p2) else '!='
print(' ', n1, eq, n2)
print('\nEdge to perimeter format translations:')
edge_d = {
'E': {(1, 11), (7, 11), (1, 7)},
'F': {(11, 23), (1, 17), (17, 23), (1, 11)},
'G': {(8, 14), (17, 19), (10, 12), (10, 14), (12, 17), (8, 18), (18, 19)},
'H': {(1, 3), (9, 11), (3, 11), (1, 11)}
}
for name, edges in edge_d.items():
print(f" {name}: {edges}\n -> {edge_to_periphery(edges)}")