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Source. Theorem 5.5, p. 43, of Shmuel Onn, Convex Discrete Optimization, arXiv:math/0703575v1 [math.OC] (20 March 2007), published in the Encyclopedia of Optimization (2009), 513--550, as identified on the source card. Labels and pages are those of the arXiv preprint.

Setting

The nn-fold matrix A(n)A^{(n)} is defined on the Theorem 4.11 page, and the comparison oracle and the meaning of solves on the Theorem 2.4 page. For this theorem the paper restates (p. 43) that the algorithm returns an optimal solution, or asserts that the program is infeasible, or asserts that the underlying polyhedron is unbounded.

Statement

Theorem 5.5 (p. 43). Fix dd and an (r+s)×t(r+s)\times t integer matrix AA. There is a polynomial time algorithm that, given nn, bounds l,u∈Z∞ntl,u\in\mathbb Z_\infty^{nt}, w1,…,wd∈Zntw_1,\ldots,w_d\in\mathbb Z^{nt}, b∈Zr+nsb\in\mathbb Z^{r+ns}, and a convex c:Rd→Rc:\mathbb R^d\to\mathbb R presented by a comparison oracle, with input encoded as [⟨l,u,w1,…,wd,b⟩][\langle l,u,w_1,\ldots,w_d,b\rangle], solves

max⁡{c(w1x,…,wdx):x∈Znt, A(n)x=b, l≤x≤u}.\max\{c(w_1x,\ldots,w_dx):x\in\mathbb Z^{nt},\ A^{(n)}x=b,\ l\le x\le u\}.

The overview (p. 7) calls it the main theorem of Section 5 and an extension of Theorem 4.11.

Proof pointer

Pp. 43--44. Linear programming over the relaxation either shows the polyhedron unbounded or gives a radius bound ρ\rho whose length is polynomial. Theorem 4.11 then serves as a linear optimization oracle for the integer points; Theorem 4.7 (p. 32) computes G(A(n))\mathcal G(A^{(n)}), which covers all edge-directions of their convex hull by Lemma 5.3 (p. 42, from Lemma 4.2); and Theorem 2.4 finishes.

Dependencies

Theorem 2.4, Theorem 4.11, Theorem 4.7 and Lemma 5.3. Read depth: claims checked; the statement was read clause by clause, the proof for its structure.

Bears on

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