pystra.systems.KOfNSystem#

Use it: User guide · Worked example · Theory

class KOfNSystem(children, k, name=None)[source]#

Bases: System

A system that fails when at least k child events fail.

Parameters:

children (Iterable[Component | System | LimitState | Callable[..., Any]]) – Child components or subsystems.
k (int) – Number of failed children required for system failure.
name (str | None) – System name.

Notes

This event-counting representation is intended for simulation, enumeration, and topology construction. Its equivalent limit-state value preserves the failure sign but is discontinuous, so it is generally not a smooth FORM/SORM limit state.

Methods

`as_limit_state`	Return the composed system as a PySTRA `LimitState`.
`component_failure_masks`	Return failure masks for each leaf component.
`component_values`	Evaluate all leaf component limit states.
`evaluate`	Evaluate the equivalent scalar system limit state.
`failure_mask`	Return a boolean mask where the system is failed.
`get_limit_state`	Return the composed system as a PySTRA `LimitState`.
`iter_components`	Yield all leaf components in the system.

as_limit_state()#

Return the composed system as a PySTRA LimitState.

Return type:: LimitState

component_failure_masks(**kwargs)#

Return failure masks for each leaf component.

Return type:: dict[str, bool | ndarray]

component_values(**kwargs)#

Evaluate all leaf component limit states.

Returns:: Mapping component names to their evaluated limit-state values.
Return type:: dict[str, ndarray]
Raises:: ValueError – If duplicate component names would make the mapping ambiguous.

property components: tuple[Component, ...]#: Flat tuple of all leaf components in the system.

evaluate(**kwargs)#

Evaluate the equivalent scalar system limit state.

Return type:: float | ndarray

failure_mask(**kwargs)#

Return a boolean mask where the system is failed.

Return type:: bool | ndarray

get_limit_state()#

Return the composed system as a PySTRA LimitState.

This legacy-style alias mirrors the existing PySTRA getter naming.

Return type:: LimitState

iter_components()#

Yield all leaf components in the system.

Return type:: Iterator[Component]