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arXiv · 2507.01434

An Optimal Least-Square Solver For Scaled Partial-Isometric Linear Systems

Suvendu Kar·Murugesan Venkatapathi
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Abstract

We present an $O(mn)$ direct least-squares solver for $m \times n$ linear systems with a scaled partial isometry. The proposed algorithm is also useful when the system is block diagonal and each block is a scaled partial isometry with distinct scaling factors. We also include numerical experiments as a demonstration.

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Suvendu Kar, Murugesan Venkatapathi. 2025-07-02. An Optimal Least-Square Solver For Scaled Partial-Isometric Linear Systems. https://arxiv.org/abs/2507.01434

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