Example: ExactI (neural fit to a known reference)

This example fits the PINN to a synthetic target to verify that the learned solution reproduces a known curve.

• Diffusivity: D(theta) = (1 - log(theta)) / 2
• Domain: o ∈ [0, 20]
• Reference: theta_ref(o) = exp(-o)
• Bounds: i = 0, b = 1

How to run

From the command line: ```bash python -m frontx.examples.exacti