Your first run

A small closed metal box is a useful installation check. A short electric-current pulse excites the field, the walls reflect it, and a probe records Ez over time. There is no port or absorbing boundary in this model.

pip install rfx-fdtd

Select the documentation version matching your installation using the version links above. For this development documentation, install the source revision identified there if you need its exact API.

Copy the following into a Python file and run it. This block is generated from the repository’s examples/quickstart/hello_world.py; its builder and execution are checked by the existing example tests.

from rfx import GaussianPulse, Simulation

sim = Simulation(
    freq_max=10e9,
    domain=(0.02, 0.02, 0.02),
    dx=2e-3,
    boundary="pec",
)
sim.add_source(
    (0.01, 0.01, 0.01),
    "ez",
    waveform=GaussianPulse(f0=5e9, bandwidth=0.8),
    amplitude_kind="current",
)
sim.add_probe((0.014, 0.01, 0.01), "ez")

preflight = sim.preflight()
print(preflight.format())
preflight.raise_for_failure()
n_steps = 120
result = sim.run(n_steps=n_steps, compute_s_params=False)
print(result.time_series.shape)

The model is a 20 mm vacuum cube with perfectly conducting (PEC) walls and 2 mm cells. Positions and dimensions are in metres. The waveform’s centre frequency is in hertz, and amplitude_kind="current" makes the excitation a current in amperes.

result.time_series has shape (120, 1): one row per time step, one column per probe. The probe is two cells away from the source. result.dt is the time between rows. The pulse reflects in the lossless closed box, so continued oscillation is expected; this is not an absorption or decay demonstration.

Preflight findings describe the model before it runs. Read warnings as well as errors. Completing these 120 steps checks the installation and API use; it does not establish an accurate resonance, Q, or a mesh-converged electromagnetic result.

• Visual manual: connect structures, field movies and measurements.
• Quick start: add a material and absorbing boundaries, then record two probes.
• Examples: choose a runnable model for your application.