# SPDX-FileCopyrightText: 2026 John C. Travers and contributors
#
# SPDX-License-Identifier: GPL-3.0-or-later
"""The calibration's synthetic problems (SEP 46 section 6.3).
Five problems that solprop ships, so that a calibration never needs a user's
simulation: a GNLSE with Raman response and self-steepening, a four-mode helium
capillary with plasma, a mode-averaged hydrogen capillary with Raman response, a
radial argon filament with plasma and a one-dimensional free-space line. Together they
exercise every CPU operation class: stage passes, responses with short and long
columns, modal and dense products, Raman histories, plasma columns, radial and
temporal transforms. Each is adapted from the benchmark tracking set's case of the
same physics (``benchmarks/builders.py``), with no noise so that every candidate does
the same work, and with a *scale* that sizes its grid: the time window for the
one-dimensional problems and the transverse count for the spatial ones. A run times
their trial steps (``StepDriver.timed_step``), never a propagation.
Four of them also come at production size (``*_large``), as large as the tracking
set's cases of their kind: on these alone a narrower team or a higher threshold that
wins on the small problems shows what it costs a production run. On 16 cores of a
Google Axion, a team of 8 won the small problems by 16 % and ran the tracking set's
large cases up to 1.8 times slower (SEP 46 Part II).
"""
from __future__ import annotations
import dataclasses
import math
from collections.abc import Callable
from typing import TYPE_CHECKING
if TYPE_CHECKING:
from solprop.driver import Simulation
__all__ = ["PROBLEMS", "build"]
def _gnlse(scale: float) -> Simulation:
"""Build Dudley, Genty and Coen's soliton fission on a `scale` x 3 ps window.
The dispersion coefficients follow J. M. Dudley, G. Genty and S. Coen, Rev. Mod.
Phys. 78, 1135 (2006), doi:10.1103/RevModPhys.78.1135, section III, as the
benchmark case does.
Parameters
----------
scale : float
The window's size relative to the standard one.
Returns
-------
solprop.driver.Simulation
The simulation.
"""
from solprop.driver import Simulation # noqa: PLC0415 - imports the physics
return Simulation.from_gnlse(
0.11,
0.15,
[
0.0,
0.0,
-11.830e-27,
8.1038e-41,
-9.5205e-56,
2.0737e-70,
-5.3943e-85,
1.3486e-99,
-2.5495e-114,
3.0524e-129,
-1.7140e-144,
],
wavelength=835e-9,
fwhm=50e-15,
shape="sech",
peak_power=10e3,
raman=True,
shock=True,
noise=None,
backend="native",
wavelength_limits=(400e-9, 2e-6),
trange=3e-12 * scale,
)
def _capillary(scale: float) -> Simulation:
"""Build four modes of a helium capillary with plasma, on `scale` x 200 fs.
Parameters
----------
scale : float
The window's size relative to the standard one.
Returns
-------
solprop.driver.Simulation
The simulation.
"""
from solprop.driver import Simulation # noqa: PLC0415 - imports the physics
return Simulation.from_capillary(
125e-6,
1.5,
"He",
(0.8, 0.0),
wavelength=800e-9,
fwhm=7.5e-15,
energy=275e-6,
modes=4,
noise=None,
backend="native",
wavelength_limits=(90e-9, 4e-6),
trange=200e-15 * scale,
)
def _averaged(scale: float) -> Simulation:
"""Build a mode-averaged hydrogen capillary with Raman, on `scale` x 800 fs.
Parameters
----------
scale : float
The window's size relative to the standard one.
Returns
-------
solprop.driver.Simulation
The simulation.
"""
from solprop.driver import Simulation # noqa: PLC0415 - imports the physics
return Simulation.from_capillary(
20e-6,
0.4,
"H2",
10.0,
wavelength=1030e-9,
fwhm=40e-15,
energy=3e-6,
loss=False,
plasma=False,
modes=1,
mode_average=True,
noise=None,
backend="native",
wavelength_limits=(200e-9, 4e-6),
trange=800e-15 * scale,
)
def _spatial(kind: str, scale: float) -> Simulation:
"""Build an argon filament on a radial grid, or Kerr focusing on a line.
Parameters
----------
kind : str
``"radial"`` or ``"line"``.
scale : float
The transverse count relative to the standard one.
Returns
-------
solprop.driver.Simulation
The simulation.
"""
import numpy as np # noqa: PLC0415
from solprop.constants import C # noqa: PLC0415
from solprop.driver import Simulation, SimulationSettings # noqa: PLC0415
from solprop.grid import FieldGrid, LineGrid, RadialGrid # noqa: PLC0415
from solprop.nonlinear.optmat_rates import OptmatRate # noqa: PLC0415
from solprop.nonlinear.responses import ( # noqa: PLC0415
KerrResponse,
PlasmaResponse,
)
from solprop.physdata import gamma3 # noqa: PLC0415
from solprop.pulses import GaussianPulse, SpatialPulse # noqa: PLC0415
from solprop.spatial import SpatialMedium, critical_power # noqa: PLC0415
radial = kind == "radial"
length = 0.01
grid = FieldGrid.from_limits(
length,
800e-9,
(350e-9, 2e-6) if radial else (500e-9, 1.6e-6),
150e-15,
)
medium = SpatialMedium("Ar", 1.0)
chi3 = gamma3("Ar", wavelength=800e-9)
density = float(medium.density(np.array([0.0]))[0])
carrier = 2 * math.pi * C / 800e-9
index = float(np.real(medium.index(np.array([carrier]))[0]))
power = (3.0 if radial else 3000.0) * critical_power(
800e-9, chi3 * density, index=index
)
energy = power * 30e-15 * math.sqrt(math.pi / (4 * math.log(2)))
pulse = SpatialPulse(
GaussianPulse(wavelength=800e-9, fwhm=30e-15, energy=energy), 100e-6
)
responses: list[KerrResponse | PlasmaResponse] = [KerrResponse(chi3, thg=False)]
settings = SimulationSettings(
save_planes=[length],
dz_max=length,
dz_init=length * 1e-4,
auto_init=True,
backend="native",
)
if radial:
responses.append(PlasmaResponse("Ar", OptmatRate("Ar", 800e-9)))
settings = dataclasses.replace(settings, ionisation_field_range=(1e7, 1e11))
return Simulation.from_radial(
grid,
RadialGrid(1.5e-3, max(16, 2 * round(32 * scale))),
medium,
responses,
pulse,
settings=settings,
noise=None,
)
return Simulation.from_free(
grid,
LineGrid(1e-3, max(32, round(128 * scale))),
medium,
responses,
pulse,
settings=settings,
)
PROBLEMS: dict[str, Callable[[float], Simulation]] = {
"gnlse": _gnlse,
"capillary": _capillary,
"averaged": _averaged,
"radial": lambda scale: _spatial("radial", scale),
"line": lambda scale: _spatial("line", scale),
# Production sizes: 16384 samples (the Raman GNLSE case), four modes on 5120
# samples (the resonant dispersive wave case), 384 radial nodes (the filament
# case), and 4096 columns standing in for the Kerr beams' many columns.
"gnlse_large": lambda scale: _gnlse(4.0 * scale),
"capillary_large": lambda scale: _capillary(2.0 * scale),
"radial_large": lambda scale: _spatial("radial", 6.0 * scale),
"line_large": lambda scale: _spatial("line", 32.0 * scale),
}
"""The calibration problems, each built at a scale (1 is the standard size)."""
[docs]
def build(name: str, scale: float = 1.0) -> Simulation:
"""Build one calibration problem at a scale of its standard size.
Parameters
----------
name : str
One of :data:`PROBLEMS`.
scale : float, optional
Its grid's size relative to the standard one: the time window of the
one-dimensional problems, the transverse count of the spatial ones.
Returns
-------
solprop.driver.Simulation
The simulation, on the native backend, without noise.
Raises
------
KeyError
For an unknown name.
"""
return PROBLEMS[name](scale)