pystra.sensitivity#

Sensitivity analysis of the reliability index.

This module computes the sensitivity of the FORM reliability index with respect to each distribution parameter declared by Distribution.sensitivity_params (by default the mean and standard deviation, but subclasses may add shape parameters, etc.).

Two methods are available, selected via the numerical flag of SensitivityAnalysis.run():

  • Finite difference (numerical=True, default): perturbs each parameter and re-runs FORM. Simple but expensive.

  • Closed-form (numerical=False): post-processes a single FORM run using the Cholesky-differentiation approach of Bourinet (2017) [Bourinet2017]. Also computes correlation sensitivities. Faster and more accurate, especially when the number of variables is large.

Classes

SensitivityAnalysis

Sensitivity analysis for the FORM reliability index.