def test_from_polygon_without_enough_tolerance():
poly = load_wkt('POLYGON ((0 0, 0.5 0, 0.5 0.5, 0 0.5, 0 0))')
with pytest.raises(ValueError) as exc:
voronoi_diagram(poly, tolerance=0.6)
assert "Could not create Voronoi Diagram with the specified inputs" in str(exc.value)
assert "Try running again with default tolerance value." in str(exc.value)
def test_from_polygon_without_floating_point_coordinates():
poly = load_wkt('POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))')
with pytest.raises(ValueError) as exc:
voronoi_diagram(poly, tolerance=0.1)
assert "Could not create Voronoi Diagram with the specified inputs" in str(exc.value)
assert "Try running again with default tolerance value." in str(exc.value)
def test_from_multipoint_with_tolerace_without_floating_point_coordinates():
"""This multipoint will not work with a tolerance value."""
mp = load_wkt('MULTIPOINT (0 0, 1 0, 1 2, 0 1)')
with pytest.raises(ValueError) as exc:
voronoi_diagram(mp, tolerance=0.1)
assert "Could not create Voronoi Diagram with the specified inputs" in str(exc.value)
assert "Try running again with default tolerance value." in str(exc.value)
def test_from_multipoint_without_floating_point_coordinates():
"""A Multipoint with the same "shape" as the above Polygon raises the same error..."""
mp = load_wkt('MULTIPOINT (0 0, 1 0, 1 1, 0 1)')
with pytest.raises(ValueError) as exc:
voronoi_diagram(mp, tolerance=0.1)
assert "Could not create Voronoi Diagram with the specified inputs" in str(exc.value)
assert "Try running again with default tolerance value." in str(exc.value)
def test_smaller_envelope():
mp = MultiPoint(points=[(0.5, 0.5), (1.0, 1.0)])
poly = load_wkt('POLYGON ((0 0, 0.5 0, 0.5 0.5, 0 0.5, 0 0))')
regions = voronoi_diagram(mp, envelope=poly)
assert len(regions.geoms) == 2
assert sum(r.area for r in regions.geoms) > poly.area
def test_larger_envelope():
"""When the envelope we specify is larger than the
area of the input feature, the created regions should
expand to fill that area."""
mp = MultiPoint(points=[(0.5, 0.5), (1.0, 1.0)])
poly = load_wkt('POLYGON ((0 0, 2 0, 2 2, 0 2, 0 0))')
regions = voronoi_diagram(mp, envelope=poly)
assert len(regions.geoms) == 2
assert sum(r.area for r in regions.geoms) == poly.area
def test_from_polygon_with_enough_tolerance():
poly = load_wkt('POLYGON ((0 0, 0.5 0, 0.5 0.5, 0 0.5, 0 0))')
regions = voronoi_diagram(poly, tolerance=1.0)
assert len(regions.geoms) == 2
def test_from_polygon():
poly = load_wkt('POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))')
regions = voronoi_diagram(poly)
assert len(regions.geoms) == 4
def test_edges():
mp = MultiPoint(points=[(0.5, 0.5), (1.0, 1.0)])
regions = voronoi_diagram(mp, edges=True)
assert len(regions.geoms) == 1
assert all(r.type == 'LineString' for r in regions.geoms)
def test_two_regions():
mp = MultiPoint(points=[(0.5, 0.5), (1.0, 1.0)])
regions = voronoi_diagram(mp)
assert len(regions.geoms) == 2
def test_from_multipoint_without_tolerace_without_floating_point_coordinates():
"""But it's fine without it."""
mp = load_wkt('MULTIPOINT (0 0, 1 0, 1 2, 0 1)')
regions = voronoi_diagram(mp)
assert len(regions.geoms) == 4
def test_no_regions():
mp = MultiPoint(points=[(0.5, 0.5)])
with np.errstate(invalid="ignore"):
regions = voronoi_diagram(mp)
assert len(regions.geoms) == 0
def test_no_regions():
mp = MultiPoint(points=[(0.5, 0.5)])
regions = voronoi_diagram(mp)
assert len(regions) == 0
from shapely.geometry import MultiPoint
from shapely.ops import voronoi_diagram
from matplotlib import pyplot
from descartes.patch import PolygonPatch
from figures import SIZE, BLUE, GRAY, set_limits
points = MultiPoint([(0, 0), (1, 1), (0, 2), (2, 2), (3, 1), (1, 0)])
regions = voronoi_diagram(points)
fig = pyplot.figure(1, figsize=SIZE, dpi=90)
fig.set_frameon(True)
ax = fig.add_subplot(111)
for region in regions:
patch = PolygonPatch(region, facecolor=BLUE, edgecolor=BLUE, alpha=0.5, zorder=2)
ax.add_patch(patch)
for point in points:
pyplot.plot(point.x, point.y, 'o', color=GRAY)
set_limits(ax, -1, 4, -1, 3)
pyplot.show()