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arXiv · 2601.01081

SaddleScape V1.0: A Python Package for Constructing Solution Landscapes via High-index Saddle Dynamics

Yuyang Liu·Hua Su·Zixiang Xiao·Lei Zhang·Jin Zhao
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Abstract

We present SaddleScape V1.0, a Python software package designed for the exploration and construction of solution landscapes in complex systems. The package implements the High-index Saddle Dynamics (HiSD) framework and its variants, including the Generalized HiSD for non-gradient systems and the Accelerated HiSD. SaddleScape V1.0 enables the systematic identification of critical points, including both local minima and high-index saddle points, by dynamically updating both the state estimate and an associated subspace characterizing the saddle's local manifold. It supports both gradient systems, defined by energy functions/functionals, and general non-gradient autonomous dynamical systems. Key features include automatic differentiation for symbolic inputs, numerical approximation techniques for Hessian-vector products, diverse eigenvalue solvers, and algorithms for constructing solution landscapes. The software offers a user-friendly interface with flexible parameter configuration, tools for trajectory and landscape visualization, and data export capabilities. By providing an efficient and accessible implementation of advanced saddle dynamics, SaddleScape V1.0 facilitates the construction of solution landscapes, empowering researchers in various scientific disciplines to gain deeper insights into the hierarchical structure of complex systems. The source code is available at the repository https://github.com/HiSDpackage/saddlescape. The package's introductory website is available at https://hisdpackage.github.io/saddlescape.

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Yuyang Liu, Hua Su, Zixiang Xiao, Lei Zhang, Jin Zhao. 2026-01-03. SaddleScape V1.0: A Python Package for Constructing Solution Landscapes via High-index Saddle Dynamics. https://arxiv.org/abs/2601.01081

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