SimulationProfile class final

What a simulation promises about its numbers, and so what may be done with a run of it.

Two profiles in 1.0, and the set is open.

deterministic: the engine's Portable maths, float-compatible, so the same tape gives the same bits on every platform. Rollback across machines, a server that verifies a run by replaying it, and one SimulationVersion per release rest on it. A game is played on it, and so is a laboratory a server checks by replay.
accurate: double precision and adaptive integrators inside the fixed step, held to analytic tests rather than to bits. A laboratory or a twin that demonstrates is run on it, and ships poses instead of a tape to replay.

Ask a capability, never which profile it is. A later release, or an outside package, may add a profile (SimulationProfile('acme.reference', …) is a value like these two), so code that decides something checks isBitExact, usesDoublePrecision or allowsAdaptiveSteps. The determinism rule in this repository asks isBitExact, not == deterministic.

Written by its name, which is set here and never taken from a Dart identifier: a file or a hello that carries the profile carries that word.

Bare names are the engine's (D23). A profile is one simulation to every tape and hello by its name alone, so a plugin's is <namespace>.<name> (acme.warming), and a later release's fast cannot be one a plugin already gave other flags; a subsystem a plugin registers under a profile outside its namespace is refused.

Constructors

SimulationProfile(String name, {required bool isBitExact, required bool usesDoublePrecision, required bool allowsAdaptiveSteps}): A profile called name with these capabilities. Two profiles are equal when their names and capabilities are.
const

Properties

allowsAdaptiveSteps → bool: Whether an integrator may take steps of its own inside the loop's fixed step, as many as the error it is held to asks for.
final
hashCode → int: The hash code for this object.
no setteroverride
isBitExact → bool: Whether the same inputs give the same bits on every platform and build of one SimulationVersion: what rollback between machines, a replay and a server's verification by replay rest on.
final
name → String: The wire name: what a file, a tape or a hello writes for it.
final
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
usesDoublePrecision → bool: Whether the state is kept and stepped in double precision rather than the float-compatible Portable maths.
final

Methods

noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
toJson() → String: name, as a document writes the profile.
toString() → String: A string representation of this object.
override

Operators

operator ==(Object other) → bool: The equality operator.
override

Static Methods

byName(String name) → SimulationProfile?: The value called name, or null for a name this version does not know, which is what a file written by a later version can carry.
parse(String name, {Iterable<SimulationProfile> known = values}) → SimulationProfile: The profile name writes. known is where it is looked for: this release's values unless a caller adds its own. Throws a DocumentFormatException naming the known ones for any other word, rather than guessing a default: a run read under the wrong promise is verified, or not, for the wrong reason.

Constants

accurate → const SimulationProfile: Double precision and adaptive integrators, held to analytic tests: no promise about bits across platforms.
deterministic → const SimulationProfile: Portable maths, the same bits on every platform: rollback, replay and verification by replay.
values → const List<SimulationProfile>: The profiles this release defines, in the order they were added.