def test_differnet_point(self):
self.assertEqual(
geo.Point(*utils.get_middle_point(0, 0, 0.2, -0.2)),
geo.Point(0.1, -0.1),
)
self.assertEqual(
geo.Point(*utils.get_middle_point(20, 40, 20.02, 40)),
geo.Point(20.01, 40)
)
def test_international_date_line(self):
self.assertEqual(
geo.Point(*utils.get_middle_point(-178, 10, 178, -10)),
geo.Point(180, 0)
)
self.assertEqual(
geo.Point(*utils.get_middle_point(-179, 43, 179, 43)),
geo.Point(180, 43.004353)
)
def test_same_points(self):
self.assertEqual(
geo.Point(*utils.get_middle_point(1.2, -1.4, 1.2, -1.4)),
geo.Point(1.2, -1.4)
)
self.assertEqual(
geo.Point(*utils.get_middle_point(-150.33, 22.1, -150.33, 22.1)),
geo.Point(-150.33, 22.1)
)
def _get_top_edge_centroid(self):
"""
Overrides :meth:`superclass' method
<nhlib.geo.surface.base.BaseSurface._get_top_edge_centroid>`
in order to avoid creating a mesh.
"""
lon, lat = geo_utils.get_middle_point(
self.corner_lons[0], self.corner_lats[0],
self.corner_lons[1], self.corner_lats[1]
)
return Point(lon, lat, self.corner_depths[0])
def get_middle_point(self):
"""
Return the middle point of the mesh.
:returns:
An instance of :class:`~nhlib.geo.point.Point`.
The middle point is taken from the middle row and a middle column
of the mesh if there are odd number of both. Otherwise the geometric
mean point of two or four middle points.
"""
num_rows, num_cols = self.lons.shape
mid_row = num_rows // 2
depth = 0
if num_rows & 1 == 1:
# there are odd number of rows
mid_col = num_cols // 2
if num_cols & 1 == 1:
# odd number of columns, we can easily take
# the middle point
if self.depths is not None:
depth = self.depths[mid_row][mid_col]
return Point(self.lons[mid_row][mid_col],
self.lats[mid_row][mid_col], depth)
else:
# even number of columns, need to take two middle
# points on the middle row
lon1, lon2 = self.lons[mid_row][mid_col - 1 : mid_col + 1]
lat1, lat2 = self.lats[mid_row][mid_col - 1 : mid_col + 1]
if self.depths is not None:
depth1 = self.depths[mid_row][mid_col - 1]
depth2 = self.depths[mid_row][mid_col]
else:
# there are even number of rows. take the row just above
# and the one just below the middle and find middle point
# of each
submesh1 = self[mid_row - 1 : mid_row]
submesh2 = self[mid_row : mid_row + 1]
p1, p2 = submesh1.get_middle_point(), submesh2.get_middle_point()
lon1, lat1, depth1 = p1.longitude, p1.latitude, p1.depth
lon2, lat2, depth2 = p2.longitude, p2.latitude, p2.depth
# we need to find the middle between two points
if self.depths is not None:
depth = (depth1 + depth2) / 2.0
lon, lat = geo_utils.get_middle_point(lon1, lat1, lon2, lat2)
return Point(lon, lat, depth)
