def test_density(fieldset, mode, area_scale):
lons, lats = np.meshgrid(np.linspace(0.05, 0.95, 10), np.linspace(-30, 30, 20))
pset = ParticleSet(fieldset, pclass=ptype[mode], lon=lons, lat=lats)
arr = pset.density(area_scale=area_scale)
if area_scale:
assert np.allclose(arr, 1 / fieldset.U.cell_areas(), rtol=1e-3) # check that density equals 1/area
else:
assert(np.sum(arr) == lons.size) # check conservation of particles
inds = np.where(arr)
for i in range(len(inds[0])): # check locations (low atol because of coarse grid)
assert np.allclose(fieldset.U.lon[inds[1][i]], pset[i].lon, atol=fieldset.U.lon[1]-fieldset.U.lon[0])
assert np.allclose(fieldset.U.lat[inds[0][i]], pset[i].lat, atol=fieldset.U.lat[1]-fieldset.U.lat[0])
def test_density(grid, mode, npart=10):
pset = ParticleSet(grid,
pclass=ptype[mode],
lon=np.linspace(0, 1, npart, dtype=np.float32),
lat=0.5 * np.ones(npart, dtype=np.float32))
arr = pset.density(area_scale=False)
assert (np.sum(arr) == npart) # check conservation of particles
inds = zip(*np.where(arr))
for i in range(
len(inds)): # check locations (low rtol because of coarse grid)
assert np.allclose(grid.U.lon[inds[i][0]], pset[i].lon, rtol=1e-1)
assert np.allclose(grid.U.lat[inds[i][1]], pset[i].lat, rtol=1e-1)
def test_density(fieldset, mode):
lons, lats = np.meshgrid(fieldset.U.lon[0], fieldset.U.lat)
pset = ParticleSet(fieldset, pclass=ptype[mode], lon=lons, lat=lats)
arr = pset.density(area_scale=False) # Not scaling by area
assert (np.sum(arr) == fieldset.U.lat.size
) # check conservation of particles
inds = zip(*np.where(arr))
for i in range(
len(inds)): # check locations (low rtol because of coarse grid)
assert np.allclose(fieldset.U.lon[inds[i][0]], pset[i].lon, rtol=1e-1)
assert np.allclose(fieldset.U.lat[inds[i][1]], pset[i].lat, rtol=1e-1)
arr = pset.density(area_scale=True) # Scaling by area
area = np.zeros(np.shape(fieldset.U.data[0, :, 0]), dtype=np.float32)
U = fieldset.U
V = fieldset.V
dy = (V.lon[1] - V.lon[0]) / V.units.to_target(1, V.lon[0], V.lat[0],
V.depth[0])
for y in range(len(U.lat)):
dx = (U.lon[1] - U.lon[0]) / U.units.to_target(1, U.lon[0], U.lat[y],
V.depth[0])
area[y] = dy * dx
assert ((arr[0, :] -
(1 / area)) == 0).all() # check that density equals 1/area
