Ralph Bottesch, Max W. Haslbeck, René Thiemann
Archive of Formal Proofs 2019.

AFP entry

 
Abstract

We formalize a proof of Motzkin’s transposition theorem and Farkas’ lemma in Isabelle/HOL. Our proof is based on the formalization of the simplex algorithm which, given a set of linear constraints, either returns a satisfying assignment to the problem or detects unsatisfiability. By reusing facts about the simplex algorithm we show that a set of linear constraints is unsatisfiable if and only if there is a linear combination of the constraints which evaluates to a trivially unsatisfiable inequality.

 
BibTex

@article{Farkas-AFP,
author = {Ralph Bottesch and Max W. Haslbeck and René Thiemann},
title = {Farkas' Lemma and Motzkin's Transposition Theorem},
journal = {Archive of Formal Proofs},
month = jan,
year = 2019,
note = {\url{https://isa-afp.org/entries/Farkas.html},
Formal proof development},
ISSN = {2150-914x},
}