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arXiv · 1007.5193

An algorithm to describe the solution set of any tropical linear system $A\odot x=B\odot x$

E. Lorenzo·M. J. de la Puente
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Abstract

An algorithm to give an explicit description of all the solutions to any tropical linear system $A\odot x=B\odot x$ is presented. The given system is converted into a finite (rather small) number $p$ of pairs $(S,T)$ of classical linear systems: a system $S$ of equations and a system $T$ of inequalities. The notion, introduced here, that makes $p$ small, is called compatibility. The particular feature of both $S$ and $T$ is that each item (equation or inequality) is bivariate, i.e., it involves exactly two variables; one variable with coefficient $1$, and the other one with $-1$. $S$ is solved by Gaussian elimination. We explain how to solve $T$ by a method similar to Gaussian elimination. To achieve this, we introduce the notion of sub--special matrix. The procedure applied to $T$ is, therefore, called sub--specialization.

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BibTeXRIS

E. Lorenzo, M. J. de la Puente. 2010-07-29. An algorithm to describe the solution set of any tropical linear system $A\odot x=B\odot x$. https://arxiv.org/abs/1007.5193

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