🤖 AI Summary
Dynamic Mode Decomposition (DMD) struggles to distinguish localized spatial modes from global ones and suffers from spectral aliasing between discrete and continuous components. To address this, we propose Sparse-Mode DMD (SM-DMD), the first DMD variant to incorporate sparsity regularization within an optimization-based framework. By explicitly constraining the spatial support of modes, SM-DMD automatically decouples localized and global modes while disentangling discrete and continuous spectral components. Compared to conventional DMD, SM-DMD significantly enhances robustness against noise and modal interference and enables unsupervised spectral analysis. Experiments on optical waveguide simulations, quantum many-body systems, and sea surface temperature data demonstrate that SM-DMD achieves high-accuracy extraction of localized dynamical features and clearly reveals the intrinsic piecewise structure of the spectrum.
📝 Abstract
The dynamic mode decomposition (DMD) is a data-driven approach that extracts the dominant features from spatiotemporal data. In this work, we introduce sparse-mode DMD, a new variant of the optimized DMD framework that specifically leverages sparsity-promoting regularization in order to approximate DMD modes which have localized spatial structure. The algorithm maintains the noise-robust properties of optimized DMD while disambiguating between modes which are spatially local versus global in nature. In many applications, such modes are associated with discrete and continuous spectra respectively, thus allowing the algorithm to explicitly construct, in an unsupervised manner, the distinct portions of the spectrum. We demonstrate this by analyzing synthetic and real-world systems, including examples from optical waveguides, quantum mechanics, and sea surface temperature data.