def test_get_half_edge(self):
#
# Construct Cell
#
v1 = Vertex((0,0))
v2 = Vertex((1,0))
v3 = Vertex((0,1))
h12 = HalfEdge(v1, v2)
h23 = HalfEdge(v2, v3)
h31 = HalfEdge(v3, v1)
# Check whether you get the right he's back
hes = [h12, h23, h31]
cell = Cell(hes)
for i in range(3):
self.assertEqual(cell.get_half_edge(i), hes[i])
def test_constructor(self):
"""
Constructor
"""
#
# Triangle
#
v1 = Vertex((0,0))
v2 = Vertex((1,0))
v3 = Vertex((0,1))
h12 = HalfEdge(v1, v2)
h23 = HalfEdge(v2, v3)
h31 = HalfEdge(v3, v1)
# Vertices not in order
bad_list_1 = [h12, h31, h23]
self.assertRaises(Exception, Cell, *[bad_list_1])
# Not a closed loop
bad_list_2 = [h12, h23]
self.assertRaises(Exception, Cell, *[bad_list_2])
triangle_half_edges = [h12, h23, h31]
cell = Cell(triangle_half_edges)
self.assertAlmostEqual(cell.area(),0.5)
self.assertEqual(cell.n_vertices(),3)
self.assertEqual(cell.n_half_edges(),3)
half_edge = cell.get_half_edge(0)
for i in range(3):
self.assertEqual(half_edge.next(), triangle_half_edges[(i+1)%3])
half_edge = half_edge.next()
#
# Square
#
v4 = Vertex((1,1))
h24 = HalfEdge(v2,v4)
h43 = HalfEdge(v4,v3)
square_half_edges = [h12, h24, h43, h31]
cell = Cell(square_half_edges)
self.assertAlmostEqual(cell.area(),1)
self.assertEqual(cell.n_vertices(),4)
self.assertEqual(cell.n_half_edges(),4)