Compression and Distillation of Data Quadruplets in Non-intrusive Reduced-order Modeling
Umair Zulfiqar
TL;DR
The paper develops a cohesive, data-driven, non-intrusive framework for reduced-order modeling that unifies BT and IRKA through the compression and distillation of data quadruplets. By leveraging transfer function samples and impulse responses within the Loewner framework, it introduces DD-ADI-BT, three data-driven IRKA variants (CT/DT) using frequency-, impulse-, or transfer-function data, and PORK-based DT methods, all without requiring new samples at every iteration. The methods show performance comparable to intrusive BT and IRKA across continuous-time and discrete-time benchmarks, while providing a unifying perspective on data-driven interpolation as a compression/distillation process. This approach enables practical MOR from available data and suggests a versatile route for data-driven model reduction in large-scale systems.
Abstract
This paper introduces a quadrature-free, data-driven approach to balanced truncation for both continuous-time and discrete-time systems. The method non-intrusively constructs reduced-order models using available transfer function samples from the right half of the $s$-plane. It is highlighted that the proposed data-driven balanced truncation and existing quadrature-based balanced truncation algorithms share a common feature: both compress their respective data quadruplets to derive reduced-order models. Additionally, it is demonstrated that by using different compression strategies, these quadruplets can be utilized to develop three data-driven formulations of the IRKA for both continuous-time and discrete-time systems. These formulations non-intrusively generate reduced models using transfer function samples from the $jω$-axis or the right half of the $s$-plane, or impulse response samples. Notably, these IRKA formulations eliminate the necessity of computing new transfer function samples as IRKA iteratively updates the interpolation points. The efficacy of the proposed algorithms is validated through numerical examples, which show that the proposed data-driven approaches perform comparably to their intrusive counterparts.
