Module: tide.callbacks

Callback state objects for inspecting forward and backward propagation.

Classes

• CallbackState

Types

• Callback

Functions

• create_callback_state

Callback Type

Callback is a callable with this pattern:

def callback(state: CallbackState) -> None:
    ...

CallbackState

Core properties: - step: current time index - nt: total time steps - dt: time step size - is_backward: whether this is the adjoint/backward pass

Accessor methods: - get_wavefield(name, view="inner") - get_model(name, view="inner") - get_gradient(name, view="inner")

View options: - full: full padded domain - pml: model plus PML region - inner: physical model interior

create_callback_state

Factory helper for constructing CallbackState with consistent metadata.

Typical use: - Users usually do not call this directly. - It is mainly useful for testing custom callback handlers.

Practical Notes

• Use forward_callback for monitoring wave propagation statistics.
• Use backward_callback to inspect gradients and adjoint wavefields.
• Avoid expensive Python-side operations every step; use callback_frequency to thin callback cadence.