def as_flat(cls,
x_min_max=None,
shaded=False,
y_ground=Y_GROUND,
surface_params=[]):
"""Build a horizontal flat ground surface, made of 1 PV segment.
Parameters
----------
x_min_max : tuple, optional
List of minimum and maximum x coordinates for the flat surface [m]
(Default = None)
shaded : bool, optional
Shaded status of the created PV surfaces (Default = False)
y_ground : float, optional
Location of flat ground on y axis in [m] (Default = Y_GROUND)
surface_params : list of str, optional
Names of the surface parameters, eg reflectivity, total incident
irradiance, temperature, etc. (Default = [])
"""
# Get ground boundaries
if x_min_max is None:
x_min, x_max = MIN_X_GROUND, MAX_X_GROUND
else:
x_min, x_max = x_min_max
# Create PV segment for flat ground
coords = [(x_min, y_ground), (x_max, y_ground)]
seg = PVSegment.from_linestring_coords(coords,
shaded=shaded,
normal_vector=[0., 1.],
surface_params=surface_params)
return cls(list_segments=[seg], original_linestring=LineString(coords))
def test_cast_shadow_segment():
"""Test shadow casting on PVSegment"""
seg = PVSegment.from_linestring_coords([(0, 0), (2, 0)],
shaded=False,
index=0)
shadow = LineString([(0.5, 0), (1.5, 0)])
seg.cast_shadow(shadow)
assert seg.length == 2
assert seg.shaded_length == 1
assert seg.index == 0
def test_cast_shadow_segment_precision_error():
"""Test shadow casting on PVSegment when using inexact projection.
In shapely, need to use ``buffer`` method for the intersection to be
calculated correctly
"""
coords = [(0, 0), (3, 2)]
seg = PVSegment.from_linestring_coords(coords, shaded=False, index=0)
# Project point on line
pt = Point(0, 2)
line = seg.illum_collection.list_surfaces[0] # LineString(coords)
vector = [1, -1]
proj = projection(pt, vector, line)
# Use result of projection to create shadow
shadow = LineString([Point(0, 0), proj])
seg.cast_shadow(shadow)
np.testing.assert_almost_equal(seg.length, 3.60555127546)
np.testing.assert_almost_equal(seg.shaded_collection.length, 1.44222051019)
assert len(seg.shaded_collection.list_surfaces) == 1
assert len(seg.illum_collection.list_surfaces) == 1
np.testing.assert_almost_equal(
seg.shaded_collection.list_surfaces[0].length, 1.44222051019)
np.testing.assert_almost_equal(
seg.illum_collection.list_surfaces[0].length, 2.1633307652783933)