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2410.11430

pycvxset: A Python package for convex set manipulation

Abraham P. Vinod

wrongmedium confidenceCounterexample detected
Category
math.DS
Journal tier
Specialist/Solid
Processed
Sep 28, 2025, 12:56 AM

Audit review

The paper explicitly claims that Y ⊆ X if and only if the optimal value of program (12) is nonnegative, for the objective minimize 1 + α^T(c_Y − G_X ξ_X − c_X) − β^T b_{e,Y} subject to ||ξ_X||_∞ ≤ 1, A_{e,X} ξ_X = b_{e,X}, and ||G_Y^T α + A_{e,Y}^T β||_1 ≤ 1 (decision variables α, β, ξ_X) . A careful duality/support-function analysis shows the opposite: the program is nonnegative if and only if X ⊆ Y. A 1D counterexample (X = [−1,1], Y = [−1/2,1/2]) gives an optimal value of −1 even though Y ⊆ X holds, directly falsifying the paper’s equivalence. Hence the inclusion direction in the paper is reversed.

Referee report (LaTeX)

\textbf{Recommendation:} major revisions

\textbf{Journal Tier:} specialist/solid

\textbf{Justification:}

The package is timely and useful, but the exact containment check between two constrained zonotopes is stated with the wrong inclusion direction. Since correctness is central to a toolbox paper, the equivalence must be corrected and briefly justified. The fix is straightforward (swap X and Y) and does not undermine the broader contribution, but it is essential.