def test_grid_limits():
X = [11.2, 11.8, 12.2, 12.3]
Y = [0.8, 1.2, 1.4, 3.1]
i0, i1, j0, j1 = 10, 14, 0, 2
C = cellcount(X, Y, grid_limits=(i0, i1, j0, j1))
assert C.shape == (j1 - j0, i1 - i0) # (2, 4)
assert C.sum() == len(X) - 1 # 3, one point outside
assert (C == [[0, 0, 0, 0], [0, 1, 2, 0]]).all()
assert C.sel(X=11, Y=1) == 1
assert C.sel(X=12, Y=1) == 2
assert C.sel(X=11, Y=0) == 0
C = cellcount(X, Y, grid_limits=(12, 3))
assert C.shape == (3, 12)
assert C.sum() == 1 # Three points outside
assert C.sel(X=11, Y=1) == 1
assert C.sel(X=11, Y=0) == 0
def test_default():
X = [11.2, 11.8, 12.2, 12.3]
Y = [0.8, 1.2, 1.4, 3.1]
C = cellcount(X, Y)
assert C.shape == (3, 2)
assert C.sum() == len(X) # 4
assert (C == [[1, 2], [0, 0], [0, 1]]).all()
assert C.sel(X=11, Y=1) == 1
assert C.sel(X=12, Y=1) == 2
assert C.sel(X=12, Y=3) == 1
assert C.sel(X=11, Y=2) == 0
def test_weight():
X = [11.2, 11.8, 12.2, 12.3]
Y = [0.8, 1.2, 1.4, 3.1]
W = [1, 2, 3, 4]
C = cellcount(X, Y, W)
assert C.shape == (3, 2)
assert C.sum() == sum(W)
assert (C == [[W[0], W[1] + W[2]], [0, 0], [0, W[3]]]).all()
assert C.sel(X=11, Y=1) == W[0]
assert C.sel(X=12, Y=1) == W[1] + W[2]
assert C.sel(X=12, Y=3) == W[3]
lat = f0.variables["lat_rho"][j0:j1, i0:i1]
# Cell centers and boundaries
Xcell = np.arange(i0, i1)
Ycell = np.arange(j0, j1)
Xb = np.arange(i0 - 0.5, i1)
Yb = np.arange(j0 - 0.5, j1)
# ---------------------------
# Read and count particles
# ---------------------------
pf = ParticleFile(pfile)
X = pf.X[tframe0:tframe1]
Y = pf.Y[tframe0:tframe1]
C = cellcount(X, Y, grid_limits=(i0, i1, j0, j1))
# ------------------------- ---
# Plot particle concentration
# -----------------------------
plt.set_cmap("cool")
plt.pcolormesh(Xb, Yb, C)
plt.colorbar()
# Land mask
constmap = plt.matplotlib.colors.ListedColormap([0.2, 0.6, 0.4])
M = np.ma.masked_where(M > 0, M)
plt.pcolormesh(Xb, Yb, M, cmap=constmap)
import numpy as np
import matplotlib.pyplot as plt
from postladim import ParticleFile, cellcount
pf = ParticleFile("line.nc")
X, Y = pf.position(80)
C = cellcount(X, Y)
i0 = int(round(X.min()))
j0 = int(round(Y.min()))
jmax, imax = C.shape
x_edges = np.arange(i0 - 0.5, i0 + imax)
y_edges = np.arange(j0 - 0.5, j0 + jmax)
plt.set_cmap("magma_r")
plt.pcolormesh(x_edges, y_edges, C)
plt.colorbar()
plt.plot(X, Y, ".k")
plt.show()