def _sample_ray(ray, npoints, field):
"""
Private function that uses a ray object for calculating the field values
that will be the y-axis values in a LinePlot object.
Parameters
----------
ray : YTOrthoRay, YTRay, or LightRay
Ray object from which to sample field values
npoints : int
The number of points to sample
field : str or field tuple
The name of the field to sample
"""
start_point = ray.start_point
end_point = ray.end_point
sample_dr = (end_point - start_point) / (npoints - 1)
sample_points = [np.arange(npoints) * sample_dr[i] for i in range(3)]
sample_points = uvstack(sample_points).T + start_point
ray_coordinates = uvstack([ray[d] for d in "xyz"]).T
ray_dds = uvstack([ray["d" + d] for d in "xyz"]).T
ray_field = ray[field]
field_values = ray.ds.arr(np.zeros(npoints), ray_field.units)
for i, sample_point in enumerate(sample_points):
ray_contains = (sample_point >= (ray_coordinates - ray_dds / 2)) & (
sample_point <= (ray_coordinates + ray_dds / 2))
ray_contains = ray_contains.all(axis=-1)
# use argmax to find the first nonzero index, sometimes there
# are two indices if the sampling point happens to fall exactly at
# a cell boundary
field_values[i] = ray_field[np.argmax(ray_contains)]
dr = np.sqrt((sample_dr**2).sum())
x = np.arange(npoints) / (npoints - 1) * (dr * npoints)
return x, field_values
def test_numpy_wrappers():
a1 = YTArray([1, 2, 3], 'cm')
a2 = YTArray([2, 3, 4, 5, 6], 'cm')
a3 = YTArray([7, 8, 9, 10, 11], 'cm')
catenate_answer = [1, 2, 3, 2, 3, 4, 5, 6]
intersect_answer = [2, 3]
union_answer = [1, 2, 3, 4, 5, 6]
vstack_answer = [[2, 3, 4, 5, 6], [7, 8, 9, 10, 11]]
assert_array_equal(YTArray(catenate_answer, 'cm'), uconcatenate((a1, a2)))
assert_array_equal(catenate_answer, np.concatenate((a1, a2)))
assert_array_equal(YTArray(intersect_answer, 'cm'), uintersect1d(a1, a2))
assert_array_equal(intersect_answer, np.intersect1d(a1, a2))
assert_array_equal(YTArray(union_answer, 'cm'), uunion1d(a1, a2))
assert_array_equal(union_answer, np.union1d(a1, a2))
assert_array_equal(YTArray(catenate_answer, 'cm'), uhstack([a1, a2]))
assert_array_equal(catenate_answer, np.hstack([a1, a2]))
assert_array_equal(YTArray(vstack_answer, 'cm'), uvstack([a2, a3]))
assert_array_equal(vstack_answer, np.vstack([a2, a3]))
assert_array_equal(YTArray(vstack_answer, 'cm'), ustack([a2, a3]))
assert_array_equal(vstack_answer, np.stack([a2, a3]))
def _get_sampler_params(self, camera, render_source):
# Enforce width[1] / width[0] = 2 * resolution[1] / resolution[0]
# For stereo-type lens, images for left and right eye are pasted together,
# so the resolution of single-eye image will be 50% of the whole one.
camera.width[1] = camera.width[0] * (
2.0 * camera.resolution[1] / camera.resolution[0]
)
if self.disparity is None:
self.disparity = 3.0 * camera.width[0] / camera.resolution[0]
if render_source.zbuffer is not None:
image = render_source.zbuffer.rgba
else:
image = self.new_image(camera)
vectors_left, positions_left = self._get_positions_vectors(
camera, -self.disparity
)
vectors_right, positions_right = self._get_positions_vectors(
camera, self.disparity
)
uv = np.ones(3, dtype="float64")
image = self.new_image(camera)
vectors_comb = uvstack([vectors_left, vectors_right])
positions_comb = uvstack([positions_left, positions_right])
image.shape = (camera.resolution[0], camera.resolution[1], 4)
vectors_comb.shape = (camera.resolution[0], camera.resolution[1], 3)
positions_comb.shape = (camera.resolution[0], camera.resolution[1], 3)
sampler_params = dict(
vp_pos=positions_comb,
vp_dir=vectors_comb,
center=self.back_center,
bounds=(0.0, 1.0, 0.0, 1.0),
x_vec=uv,
y_vec=uv,
width=np.zeros(3, dtype="float64"),
image=image,
lens_type="stereo-perspective",
)
return sampler_params
def _yield_coordinates(self, data_file):
pn = "particle_position_%s"
with h5py.File(data_file.filename, 'r') as f:
units = parse_h5_attr(f[pn % "x"], "units")
x, y, z = (self.ds.arr(f[pn % ax].value.astype("float64"), units)
for ax in 'xyz')
pos = uvstack([x, y, z]).T
pos.convert_to_units('code_length')
yield 'halos', pos
def _yield_coordinates(self, data_file):
pn = "particle_position_%s"
with h5py.File(data_file.filename, mode="r") as f:
units = parse_h5_attr(f[pn % "x"], "units")
x, y, z = (self.ds.arr(f[pn % ax][()].astype("float64"), units)
for ax in "xyz")
pos = uvstack([x, y, z]).T
pos.convert_to_units("code_length")
yield "halos", pos
def _yield_coordinates(self, data_file):
with h5py.File(data_file.filename, "r") as f:
for ptype in f.keys():
if "x" not in f[ptype].keys():
continue
units = _get_position_array_units(ptype, f, "x")
x, y, z = (self.ds.arr(_get_position_array(ptype, f, ax),
units) for ax in "xyz")
pos = uvstack([x, y, z]).T
pos.convert_to_units("code_length")
yield ptype, pos
def project_to_plane(self, camera, pos, res=None):
if res is None:
res = camera.resolution
# Enforce width[1] / width[0] = 2 * resolution[1] / resolution[0]
# For stereo-type lens, images for left and right eye are pasted together,
# so the resolution of single-eye image will be 50% of the whole one.
camera.width[1] = camera.width[0] * (2. * res[1] / res[0])
if self.disparity is None:
self.disparity = 3. * camera.width[0] / camera.resolution[0]
px_left, py_left, dz_left = self._get_px_py_dz(camera, pos, res,
-self.disparity)
px_right, py_right, dz_right = self._get_px_py_dz(
camera, pos, res, self.disparity)
px = uvstack([px_left, px_right])
py = uvstack([py_left, py_right])
dz = uvstack([dz_left, dz_right])
return px, py, dz
