# Upstream-only observations
# All observations are upstream/near the source - more challenging for inference

[physics]
vx = 1.0          # Advection velocity in x
vy = 0.0          # Advection velocity in y
D = 0.05          # Diffusion coefficient
domain = [0.0, 1.0, 0.0, 1.0]  # [x_min, x_max, y_min, y_max]
c_inflow = 0.0    # Dirichlet BC at left boundary

[[sources]]
x = 0.3
y = 0.5
strength = 5.0
width = 0.08

# Observations only upstream/near the source (x <= 0.5)
# This is more challenging since advection carries info downstream

[[observations]]
x = 0.1
y = 0.9

[[observations]]
x = 0.1
y = 0.7

[[observations]]
x = 0.1
y = 0.5

[[observations]]
x = 0.1
y = 0.3

[[observations]]
x = 0.1
y = 0.1

[noise]
std = 0.005
seed = 42