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This paper shows how a basic property of unitary transformations can be used for meaningful computations. This approach immediately leads to search-type applications, where it improves the number of steps by a square-root - a simple minded…

Quantum Physics · Physics 2015-06-26 Lov K. Grover

Binary jumbled pattern matching asks to preprocess a binary string $S$ in order to answer queries $(i,j)$ which ask for a substring of $S$ that is of length $i$ and has exactly $j$ 1-bits. This problem naturally generalizes to…

Data Structures and Algorithms · Computer Science 2014-07-01 Travis Gagie , Danny Hermelin , Gad M. Landau , Oren Weimann

Rank and select queries on bitmaps are essential building bricks of many compressed data structures, including text indexes, membership and range supporting spatial data structures, compressed graphs, and more. Theoretically considered yet…

Data Structures and Algorithms · Computer Science 2016-05-13 Szymon Grabowski , Marcin Raniszewski

Constrained clustering is a semi-supervised task that employs a limited amount of labelled data, formulated as constraints, to incorporate domain-specific knowledge and to significantly improve clustering accuracy. Previous work has…

Machine Learning · Computer Science 2023-05-17 Pouya Shati , Eldan Cohen , Sheila McIlraith

We show that crowd counting can be viewed as a decomposable point querying process. This formulation enables arbitrary points as input and jointly reasons whether the points are crowd and where they locate. The querying processing, however,…

Computer Vision and Pattern Recognition · Computer Science 2023-08-29 Chengxin Liu , Hao Lu , Zhiguo Cao , Tongliang Liu

We propose a B tree representation storing $n$ keys, each of $k$ bits, in either (a) $nk + O(nk / \lg n)$ bits or (b) $nk + O(nk \lg \lg n/ \lg n)$ bits of space supporting all B tree operations in either (a) $O(\lg n )$ time or (b) $O(\lg…

Data Structures and Algorithms · Computer Science 2021-04-20 Tomohiro I , Dominik Köppl

Building concurrent spatial trees is more complicated than binary search trees since a space hierarchy should be preserved during modifications. We present a non-blocking quadtree-quadboost-that supports concurrent insert, remove, move, and…

Data Structures and Algorithms · Computer Science 2016-07-13 Keren Zhou , Guangming Tan , Wei Zhou

State-of-the-art clustering algorithms use heuristics to partition the feature space and provide little insight into the rationale for cluster membership, limiting their interpretability. In healthcare applications, the latter poses a…

Machine Learning · Statistics 2018-12-04 Dimitris Bertsimas , Agni Orfanoudaki , Holly Wiberg

Specific data compression techniques, formalized by the concept of coresets, proved to be powerful for many optimization problems. In fact, while tightly controlling the approximation error, coresets may lead to significant speed up of the…

Optimization and Control · Mathematics 2022-04-05 Maximilian Fiedler , Peter Gritzmann , Fabian Klemm

Efficient embedding virtual clusters in physical network is a challenging problem. In this paper we consider a scenario where physical network has a structure of a balanced tree. This assumption is justified by many real- world…

Distributed, Parallel, and Cluster Computing · Computer Science 2015-01-30 Carlo Fuerst , Maciej Pacut , Stefan Schmid

Minimum spanning trees (MSTs) provide a convenient representation of datasets in numerous pattern recognition activities. Moreover, they are relatively fast to compute. In this paper, we quantify the extent to which they are meaningful in…

Machine Learning · Statistics 2025-10-16 Marek Gagolewski , Anna Cena , Maciej Bartoszuk , Łukasz Brzozowski

Text clustering holds significant value across various domains due to its ability to identify patterns and group related information. Current approaches which rely heavily on a computed similarity measure between documents are often limited…

Information Retrieval · Computer Science 2025-04-09 Laurence Hirsch , Robin Hirsch , Bayode Ogunleye

Nowadays, document clustering is considered as a data intensive task due to the dramatic, fast increase in the number of available documents. Nevertheless, the features that represent those documents are also too large. The most common…

Databases · Computer Science 2015-05-13 Abdelrahman Elsayed , Hoda M. O. Mokhtar , Osama Ismail

Multi-robot path planning is difficult due to the combinatorial explosion of the search space with every new robot added. Complete search of the combined state-space soon becomes intractable. In this paper we present a novel form of…

Artificial Intelligence · Computer Science 2011-11-02 Malcolm Ross Kinsella Ryan

Recently, the retrieval models based on dense representations have been gradually applied in the first stage of the document retrieval tasks, showing better performance than traditional sparse vector space models. To obtain high efficiency,…

Information Retrieval · Computer Science 2021-08-20 Hongyin Tang , Xingwu Sun , Beihong Jin , Jingang Wang , Fuzheng Zhang , Wei Wu

We introduce dynamic smooth (a.k.a. balanced) compressed quadtrees with worst-case constant time updates in constant dimensions. We distinguish two versions of the problem. First, we show that quadtrees as a space-division data structure…

Computational Geometry · Computer Science 2018-02-23 Ivor Hoog v. d. , Elena Khramtcova , Maarten Löffler

We show how to represent sets in a linear space data structure such that expressions involving unions and intersections of sets can be computed in a worst-case efficient way. This problem has applications in e.g. information retrieval and…

Data Structures and Algorithms · Computer Science 2007-08-27 Philip Bille , Anna Pagh , Rasmus Pagh

The class of self-nested trees presents remarkable compression properties because of the systematic repetition of subtrees in their structure. In this paper, we provide a better combinatorial characterization of this specific family of…

Data Structures and Algorithms · Computer Science 2018-10-26 Romain Azaïs , Jean-Baptiste Durand , Christophe Godin

Density peaks clustering has become a nova of clustering algorithm because of its simplicity and practicality. However, there is one main drawback: it is time-consuming due to its high computational complexity. Herein, a density peaks…

Machine Learning · Statistics 2022-07-21 Yunxiao Shan , Shu Li , Fuxiang Li , Yuxin Cui , Shuai Li , Ming Zhou , Xiang Li

We present a novel deep compression algorithm to reduce the memory footprint of LiDAR point clouds. Our method exploits the sparsity and structural redundancy between points to reduce the bitrate. Towards this goal, we first encode the…

Image and Video Processing · Electrical Eng. & Systems 2021-01-12 Lila Huang , Shenlong Wang , Kelvin Wong , Jerry Liu , Raquel Urtasun