English
Related papers

Related papers: Koopman operator framework for spectral analysis a…

200 papers

PyKoopman is a Python package for the data-driven approximation of the Koopman operator associated with a dynamical system. The Koopman operator is a principled linear embedding of nonlinear dynamics and facilitates the prediction,…

Systems and Control · Electrical Eng. & Systems 2023-06-23 Shaowu Pan , Eurika Kaiser , Brian M. de Silva , J. Nathan Kutz , Steven L. Brunton

The framework of Koopman operator theory is discussed along with its connections to Dynamic Mode Decomposition (DMD) and (Kernel) Extended Dynamic Mode Decomposition (EDMD). This paper provides a succinct overview with consistent notation.…

Numerical Analysis · Mathematics 2024-10-07 Christophe Patyn , Geert Deconinck

This paper explores operators with countable, continuous, and hybrid spectra, focusing on both finite dimensional and infinite dimensional cases, particularly in non-Hermitian systems. For finite dimensional operators, a novel concept of…

Functional Analysis · Mathematics 2024-11-20 Shih-Yu Chang

Deep learning is revolutionizing weather forecasting, with new data-driven models achieving accuracy on par with operational physical models for medium-term predictions. However, these models often lack interpretability, making their…

Machine Learning · Computer Science 2024-09-11 David Millard , Arielle Carr , Stéphane Gaudreault

The Koopman operator framework offers a way to represent a nonlinear system as a linear one. The key to this simplification lies in the identification of eigenfunctions. While various data-driven algorithms have been developed for this…

Systems and Control · Electrical Eng. & Systems 2025-09-16 Xinyuan Jiang , Yan Li

Koopman linear representations have become a popular tool for control design of nonlinear systems, yet it remains unclear when such representations are exact. In this paper, we establish sufficient and necessary conditions under which a…

Optimization and Control · Mathematics 2026-02-17 Xu Shang , Masih Haseli , Jorge Cortés , Yang Zheng

Linear dynamical systems are fully characterized by their eigenspectra, accessible directly from the generator of the dynamics. For nonlinear systems governed by partial differential equations, no equivalent theory exists. We introduce Lie…

Machine Learning · Computer Science 2026-04-02 Shafayeth Jamil , Rehan Kapadia

Analyzing the long-term behavior of high-dimensional nonlinear dynamical systems remains a significant challenge. While the Koopman operator framework provides a powerful global linearization tool, current methods for approximating its…

Machine Learning · Computer Science 2025-05-28 Yuanchao Xu , Kaidi Shao , Nikos Logothetis , Zhongwei Shen

We propose a novel operator-theoretic framework to study global stability of nonlinear systems. Based on the spectral properties of the so-called Koopman operator, our approach can be regarded as a natural extension of classic linear…

Dynamical Systems · Mathematics 2015-09-11 Alexandre Mauroy , Igor Mezic

Soft robots are challenging to model and control as inherent non-linearities (e.g., elasticity and deformation), often requires complex explicit physics-based analytical modeling (e.g., a priori geometric definitions). While machine…

Robotics · Computer Science 2022-10-17 Naoto Komeno , Brendan Michael , Katharina Küchler , Edgar Anarossi , Takamitsu Matsubara

Koopman operator theory yields powerful tools for modeling, analysis, and control of nonlinear dynamical systems. Prominently, linear time-invariant (LTI) Koopman representations have been proposed to enable the application of linear…

Optimization and Control · Mathematics 2026-05-29 Johannes Heeg , Karl Worthmann

The Koopman Operator (KO) is a mathematical construct that maps nonlinear (state space) dynamics to corresponding linear dynamics in an infinite-dimensional functional space. For practical applications, finite-dimensional approximations can…

Dynamical Systems · Mathematics 2025-06-19 Craig Bakker

The Koopman linearization of measure-preserving systems or topological dynamical systems on compact spaces has proven to be extremely useful. In this article we look at dynamics given by continuous semiflows on completely regular spaces…

Functional Analysis · Mathematics 2021-04-28 Bálint Farkas , Henrik Kreidler

A popular technique used to obtain linear representations of nonlinear systems is the so-called Koopman approach, where the nonlinear dynamics are lifted to a (possibly infinite dimensional) linear space through nonlinear functions called…

Systems and Control · Electrical Eng. & Systems 2023-12-18 Lucian Cristian Iacob , Roland Tóth , Maarten Schoukens

The Koopman operator provides a principled framework for analyzing nonlinear dynamical systems through linear operator theory. Recent advances in dynamic mode decomposition (DMD) have shown that trajectory data can be used to identify…

Machine Learning · Computer Science 2026-01-21 Minchan Jeong , J. Jon Ryu , Se-Young Yun , Gregory W. Wornell

Dynamical systems provide a comprehensive way to study complex and changing behaviors across various sciences. Many modern systems are too complicated to analyze directly or we do not have access to models, driving significant interest in…

Dynamical Systems · Mathematics 2024-07-10 Matthew J. Colbrook , Igor Mezić , Alexei Stepanenko

Transfer operators offer linear representations and global, physically meaningful features of nonlinear dynamical systems. Discovering transfer operators, such as the Koopman operator, require careful crafted dictionaries of observables,…

Robotics · Computer Science 2023-08-15 Tahiya Salam , Alice Kate Li , M. Ani Hsieh

Information about the behavior of dynamical systems can often be obtained by analyzing the eigenvalues and corresponding eigenfunctions of linear operators associated with a dynamical system. Examples of such operators are the…

Dynamical Systems · Mathematics 2016-10-21 Stefan Klus , Péter Koltai , Christof Schütte

Koopman operators linearize nonlinear dynamical systems, making their spectral information of crucial interest. Numerous algorithms have been developed to approximate these spectral properties, and Dynamic Mode Decomposition (DMD) stands…

Dynamical Systems · Mathematics 2023-11-13 Matthew J. Colbrook , Qin Li , Ryan V. Raut , Alex Townsend

In a recent article, we presented a framework to control nonlinear partial differential equations (PDEs) by means of Koopman operator based reduced models and concepts from switched systems. The main idea was to transform a control system…

Optimization and Control · Mathematics 2019-05-15 Sebastian Peitz