Brick composition of a block plus parameters. More...

#include <model_spec.hpp>

Collaboration diagram for pops::ModelSpec:

Public Attributes
std::string	transport
	REQUIRED (unset): "exb" \| "compressible" \| "isothermal".

std::string	source = "none"
	"none" (default, neutral: no force) \| "potential" \| "gravity"

std::string	elliptic
	REQUIRED (unset): "charge" \| "background" \| "gravity".

double	B0 = 1.0
	ExBVelocity: magnetic field.

double	gamma = 1.4
	CompressibleFlux: adiabatic index.

double	cs2 = 0.5
	IsothermalFlux: sound speed squared.

double	vacuum_floor = 0.0
	IsothermalFlux: quasi-vacuum density floor for u=m/max(rho,floor) (ADC-77).

double	qom = 1.0
	PotentialForce / MagneticLorentzForce: q/m (sign included)

double	q = 1.0
	ChargeDensity: charge q.

double	alpha = 1.0
	BackgroundDensity: Poisson coupling.

double	n0 = 0.0
	BackgroundDensity: neutralizing background.

double	sign = 1.0
	GravityCoupling: +1 gravity, -1 electrostatic.

double	four_pi_G = 1.0
	GravityCoupling: coupling intensity.

double	rho0 = 1.0
	GravityCoupling: background.

Detailed Description

Brick composition of a block plus parameters.

The fields are only read by the relevant brick (see dispatch_model in model_factory.hpp).

CONTRACT (ADC-290): a ModelSpec carries NO silent physics default. transport and elliptic are UNSET by default (empty string) and MUST be chosen explicitly; an unset tag is rejected with a clear message by validate_model_spec (model_factory.hpp) instead of silently selecting a model (the old defaults transport="compressible" / elliptic="charge" made a default-constructed ModelSpec mean Euler + Poisson-charge by accident). source keeps the only default, "none" – the EXPLICIT, neutral "no source" choice, not a physics selection. The numeric parameters keep their defaults: each is read only once its brick has been chosen by a tag, so it can never inject physics on its own. Historical shortcuts live at the Python edge (pops.Model(...)), which always sets the three tags. See docs/adr/ADR-0001-genericity-contracts.md.

Member Data Documentation

◆ alpha

double pops::ModelSpec::alpha = 1.0

BackgroundDensity: Poisson coupling.

◆ B0

double pops::ModelSpec::B0 = 1.0

ExBVelocity: magnetic field.

◆ cs2

double pops::ModelSpec::cs2 = 0.5

IsothermalFlux: sound speed squared.

◆ elliptic

std::string pops::ModelSpec::elliptic

REQUIRED (unset): "charge" | "background" | "gravity".

◆ four_pi_G

double pops::ModelSpec::four_pi_G = 1.0

GravityCoupling: coupling intensity.

◆ gamma

double pops::ModelSpec::gamma = 1.4

CompressibleFlux: adiabatic index.

◆ n0

double pops::ModelSpec::n0 = 0.0

BackgroundDensity: neutralizing background.

◆ q

double pops::ModelSpec::q = 1.0

ChargeDensity: charge q.

◆ qom

double pops::ModelSpec::qom = 1.0

PotentialForce / MagneticLorentzForce: q/m (sign included)

◆ rho0

double pops::ModelSpec::rho0 = 1.0

GravityCoupling: background.

◆ sign

double pops::ModelSpec::sign = 1.0

GravityCoupling: +1 gravity, -1 electrostatic.

◆ source

std::string pops::ModelSpec::source = "none"

"none" (default, neutral: no force) | "potential" | "gravity"

| "magnetic"/"lorentz" | "potential_magnetic"/"potential_lorentz"

◆ transport

std::string pops::ModelSpec::transport

REQUIRED (unset): "exb" | "compressible" | "isothermal".

◆ vacuum_floor

double pops::ModelSpec::vacuum_floor = 0.0

IsothermalFlux: quasi-vacuum density floor for u=m/max(rho,floor) (ADC-77).

Set from pops.FluidState(vacuum_floor=...) at compose; INDEPENDENT of the spatial positivity_floor (deliberately decoupled – coupling them shifts the CFL dt of existing positivity_floor runs). 0 = off (bit-identical)

The documentation for this struct was generated from the following file:

include/pops/runtime/config/model_spec.hpp

ModelSpec Struct Reference¶

Public Attributes