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arXiv · 1611.06633

Two direct solvers for a system of linear equations

Michael F. Zimmer
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Abstract

A system of linear equations is normally understood as a linear mapping between two vector spaces. However, most direct solutions (e.g., QR, LU, ...) rely on the inelegant approach of back-substitution: a significant departure from such a characterization. In this paper, two new methods are introduced which respect the underlying vector space throughout, whether it be the row or column space of the coefficient matrix. Both solutions produce a generalized inverse as well as a projection operator for the null space. They also have the unique feature of admitting an online solution, which allows a solution to be computed as the data becomes available.

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Michael F. Zimmer. 2016-11-21. Two direct solvers for a system of linear equations. https://arxiv.org/abs/1611.06633

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