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arXiv · 2206.03730

A Lanczos-type procedure for tensors

S. Cipolla·S. Pozza·M. Redivo-Zaglia·N. Van Buggenhout
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Abstract

The solution of linear non-autonomous ordinary differential equation systems (also known as the time-ordered exponential) is a computationally challenging problem arising in a variety of applications. In this work, we present and study a new framework for the computation of bilinear forms involving the time-ordered exponential. Such a framework is based on an extension of the non-Hermitian Lanczos algorithm to 4-mode tensors. Detailed results concerning its theoretical properties are presented. Moreover, computational results performed on real world problems confirm the effectiveness of our approach.

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S. Cipolla, S. Pozza, M. Redivo-Zaglia, N. Van Buggenhout. 2022-06-08. A Lanczos-type procedure for tensors. https://arxiv.org/abs/2206.03730

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