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Given a set of $n$ points in the plane, and a parameter $k$, we consider the problem of computing the minimum (perimeter or area) axis-aligned rectangle enclosing $k$ points. We present the first near quadratic time algorithm for this…

Computational Geometry · Computer Science 2019-03-19 Timothy M. Chan , Sariel Har-Peled

Consider an arrangement of $k$ lines intersecting the unit square. There is some minimum scaling factor so that any placement of a rectangle with aspect ratio $1 \times p$ with $p\geq 1$ must non-transversely intersect some portion of the…

Computational Geometry · Computer Science 2022-01-05 Bradley McCoy , Eli Quist , Anna Schenfisch

For a class of polyhedrons denoted $\mathbb K_n(r,\varepsilon)$, we construct a bijective continuous area preserving map from $\mathbb K_n(r,\varepsilon)$ to the sphere $\mathbb S^{2}(r)$, together with its inverse. Then we investigate for…

Metric Geometry · Mathematics 2015-04-08 Adrian Holhoş , Daniela Roşca

We consider the problem of recovering a low-rank matrix from its clipped observations. Clipping is conceivable in many scientific areas that obstructs statistical analyses. On the other hand, matrix completion (MC) methods can recover a…

Machine Learning · Computer Science 2019-03-05 Takeshi Teshima , Miao Xu , Issei Sato , Masashi Sugiyama

We study the minimum diameter problem for a set of inexact points. By inexact, we mean that the precise location of the points is not known. Instead, the location of each point is restricted to a contineus region ($\impre$ model) or a…

Computational Geometry · Computer Science 2017-04-03 Mohammad Ghodsi , Hamid Homapour , Masoud Seddighin

We study beyond worst-case dimensionality reduction for $s$-sparse vectors. Our work is divided into two parts, each focusing on a different facet of beyond worst-case analysis: We first consider average-case guarantees. A folklore upper…

Data Structures and Algorithms · Computer Science 2025-02-28 Sandeep Silwal , David P. Woodruff , Qiuyi Zhang

Given an overcomplete dictionary $A$ and a signal $b = Ac^*$ for some sparse vector $c^*$ whose nonzero entries correspond to linearly independent columns of $A$, classical sparse signal recovery theory considers the problem of whether…

Machine Learning · Computer Science 2020-01-01 Daniel P. Robinson , Rene Vidal , Chong You

The aim of this paper is to characterize those linear maps from a von Neumann factor $\A$ into itself which preserve the extreme points of the unit ball of $\A$. For example, we show that if $\A$ is infinite, then every such linear…

Functional Analysis · Mathematics 2016-09-07 Vania Mascioni , Lajos Molnar

We investigate orthonormality-preserving, C*-conformal and conformal module mappings on Hilbert C*-modules to obtain their general structure. Orthogonality-preserving bounded module maps T act as a multiplication by an element \lambda of…

Operator Algebras · Mathematics 2025-04-29 Michael Frank , Alexander S. Mishchenko , Alexander A. Pavlov

We consider the problem of reconstructing rank-one matrices from random linear measurements, a task that appears in a variety of problems in signal processing, statistics, and machine learning. In this paper, we focus on the Alternating…

Machine Learning · Computer Science 2022-04-26 Kiryung Lee , Dominik Stöger

The optimal one-sided parametric polynomial approximants of a circular arc are considered. More precisely, the approximant must be entirely in or out of the underlying circle of an arc. The natural restriction to an arc's approximants…

Numerical Analysis · Mathematics 2025-09-03 Ada Šadl Praprotnik , Aleš Vavpetič , Emil Žagar

We investigate the orthogonality preserving property for pairs of mappings on inner product $C^*$-modules extending existing results for a single orthogonality-preserving mapping. Guided by the point of view that the $C^*$-valued inner…

Operator Algebras · Mathematics 2025-04-29 Michael Frank , M. S. Moslehian , Ali Zamani

We study approximation algorithms for the following geometric version of the maximum coverage problem: Let $\mathcal{P}$ be a set of $n$ weighted points in the plane. Let $D$ represent a planar object, such as a rectangle, or a disk. We…

Computational Geometry · Computer Science 2017-12-08 Kai Jin , Jian Li , Haitao Wang , Bowei Zhang , Ningye Zhang

We propose a method for learning topology-preserving data representations (dimensionality reduction). The method aims to provide topological similarity between the data manifold and its latent representation via enforcing the similarity in…

Machine Learning · Computer Science 2023-05-05 Ilya Trofimov , Daniil Cherniavskii , Eduard Tulchinskii , Nikita Balabin , Evgeny Burnaev , Serguei Barannikov

Orthogonal Monte Carlo (OMC) is a very effective sampling algorithm imposing structural geometric conditions (orthogonality) on samples for variance reduction. Due to its simplicity and superior performance as compared to its Quasi Monte…

Machine Learning · Computer Science 2020-05-29 Han Lin , Haoxian Chen , Tianyi Zhang , Clement Laroche , Krzysztof Choromanski

We propose a new $(1+O(\varepsilon))$-approximation algorithm with $O(n+ 1/\varepsilon^{\frac{(d-1)}{2}})$ running time for computing the diameter of a set of $n$ points in the $d$-dimensional Euclidean space for a fixed dimension $d$,…

Computational Geometry · Computer Science 2020-11-11 Mahdi Imanparast , Seyed Naser Hashemi

We consider the problem of estimating the Attention mechanism in small space, and prove the existence of coresets for it of nearly optimal size. Specifically, we show that for any set of unit-norm keys and values $(K,V)$ in $\mathbb{R}^d$,…

Data Structures and Algorithms · Computer Science 2026-05-08 Edo Liberty , Alexandr Andoni , Eldar Kleiner

This article presents a general approximation-theoretic framework to analyze measure transport algorithms for probabilistic modeling. A primary motivating application for such algorithms is sampling -- a central task in statistical…

Numerical Analysis · Mathematics 2024-09-19 Ricardo Baptista , Bamdad Hosseini , Nikola B. Kovachki , Youssef M. Marzouk , Amir Sagiv

A multiplicative $\alpha$-spanner $H$ is a subgraph of $G=(V,E)$ with the same vertices and fewer edges that preserves distances up to the factor $\alpha$, i.e., $d_H(u,v)\leq\alpha\cdot d_G(u,v)$ for all vertices $u$, $v$. While many…

Data Structures and Algorithms · Computer Science 2021-07-06 Markus Chimani , Finn Stutzenstein

Let $n_1,\ldots,n_k $ be integers larger than or equal to 2. We characterize linear maps $\phi: M_{n_1\cdots n_k}\rightarrow M_{n_1\cdots n_k}$ such that $${\mathrm rank}\,(\phi(A_1\otimes \cdots \otimes…

Functional Analysis · Mathematics 2017-01-26 Zejun Huang , Shiyu Shi , Nung-Sing Sze