phi: Structure function

In dist.structure: Structured Random Variables for Reliability System Distributions

Structure function

Description

Evaluate the coherent structure function ⁠phi: {0, 1}^m -> {0, 1}⁠ at a component state vector state. By convention state[j] = 1 means component j is functioning; phi(state) = 1 means the system is functioning.

Usage

## S3 method for class 'dist_structure'
phi(x, state)

phi(x, state)

Arguments

x	A dist_structure object.
state	Integer or logical vector of length ncomponents(x) in ⁠{0, 1}⁠.

Details

phi and min_paths() are dual primitives: if a subclass provides only ⁠phi.<class>()⁠, the default min_paths.dist_structure() enumerates minimal subsets via phi; if a subclass provides only ⁠min_paths.<class>()⁠, the default phi.dist_structure() checks whether state covers any minimal path. Subclasses providing both must keep them consistent.

Value

Integer scalar, 0 or 1.

See Also

min_paths() for the dual primitive; validate_dist_structure() for construction-time checking.

dist.structure documentation built on May 13, 2026, 1:07 a.m.