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arXiv · 2402.09983

Optimistix: modular optimisation in JAX and Equinox

Jason Rader·Terry Lyons·Patrick Kidger
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Abstract

We introduce Optimistix: a nonlinear optimisation library built in JAX and Equinox. Optimistix introduces a novel, modular approach for its minimisers and least-squares solvers. This modularity relies on new practical abstractions for optimisation which we call search and descent, and which generalise classical notions of line search, trust-region, and learning-rate algorithms. It provides high-level APIs and solvers for minimisation, nonlinear least-squares, root-finding, and fixed-point iteration. Optimistix is available at https://github.com/patrick-kidger/optimistix.

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Jason Rader, Terry Lyons, Patrick Kidger. 2024-02-15. Optimistix: modular optimisation in JAX and Equinox. https://arxiv.org/abs/2402.09983

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