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Compression of integer sets and sequences has been extensively studied for settings where elements follow a uniform probability distribution. In addition, methods exist that exploit clustering of elements in order to achieve higher…

Information Theory · Computer Science 2014-02-11 N. Jesper Larsson

An explicit algorithm for performing Schumacher's noiseless compression of quantum bits is given. This algorithm is based on a combinatorial expression for a particular bijection among binary strings. The algorithm, which adheres to the…

Quantum Physics · Physics 2009-10-30 Richard Cleve , David P. DiVincenzo

We present a new quantum Monte Carlo algorithm suitable for generically complex problems, such as systems coupled to external magnetic fields or anyons in two spatial dimensions. We find that the choice of gauge plays a nontrivial role, and…

Condensed Matter · Physics 2009-10-22 Lizeng Zhang , Geoff Canright , Ted Barnes

Detection algorithms for multiple-input multiple-output (MIMO) wireless systems based on orthogonal frequency-division multiplexing (OFDM) typically require the computation of a QR decomposition for each of the data-carrying OFDM tones. The…

Information Theory · Computer Science 2009-10-30 Davide Cescato , Helmut Bölcskei

One of the crucial generic techniques for quantum computation is amplitude encoding. Although several approaches have been proposed, each of them often requires exponential classical-computational cost or an oracle whose explicit…

Quantum Physics · Physics 2024-12-06 Taichi Kosugi , Shunsuke Daimon , Hirofumi Nishi , Shinji Tsuneyuki , Yu-ichiro Matsushita

We conducted quantum simulations of strongly correlated systems using the quantum flow (QFlow) approach, which enables sampling large sub-spaces of the Hilbert space through coupled eigenvalue problems in reduced dimensionality active…

Quantum Physics · Physics 2023-08-09 Karol Kowalski , Nicholas P. Bauman

Given a string $S$ of length $N$ on a fixed alphabet of $\sigma$ symbols, a grammar compressor produces a context-free grammar $G$ of size $n$ that generates $S$ and only $S$. In this paper we describe data structures to support the…

Data Structures and Algorithms · Computer Science 2014-08-15 Djamal Belazzougui , Simon J. Puglisi , Yasuo Tabei

In the context of the compressed sensing problem, we propose a new ensemble of sparse random matrices which allow one (i) to acquire and compress a {\rho}0-sparse signal of length N in a time linear in N and (ii) to perfectly recover the…

Information Theory · Computer Science 2013-04-15 Maria Chiara Angelini , Federico Ricci-Tersenghi , Yoshiyuki Kabashima

We suggest an all-optical scheme for the storage, retrieval and processing of a single-photon wave packet through its off-resonant Raman interaction with a series of coherent control beams. These control beams, each with distinct carrier…

Quantum Physics · Physics 2016-12-09 Xiwen Zhang , Alexey Kalachev , Philip Hemmer , Olga Kocharovskaya

Unit norm finite frames are generalizations of orthonormal bases with many applications in signal processing. An important property of a frame is its coherence, a measure of how close any two vectors of the frame are to each other. Low…

Signal Processing · Electrical Eng. & Systems 2018-06-21 Cristian Rusu , Nuria Gonzalez-Prelcic , Robert W. Heath

Sublinear time quantum algorithms have been established for many fundamental problems on strings. This work demonstrates that new, faster quantum algorithms can be designed when the string is highly compressible. We focus on two popular and…

Data Structures and Algorithms · Computer Science 2023-02-15 Daniel Gibney , Sharma V. Thankachan

The problem of quantum harmonic oscillator with "regular+random" square frequency, subjected to "regular+random external force, is considered in framework of representation of the wave function by complex-valued random process. Average…

Quantum Physics · Physics 2007-05-23 A. S. Gevorkyan , A. A. Udalov

We show that the number of distinct squares in a packed string of length $n$ over an alphabet of size $\sigma$ can be computed in $O(n/\log_\sigma n)$ time in the word-RAM model. This paper is the first to introduce a sublinear-time…

Data Structures and Algorithms · Computer Science 2025-09-03 Panagiotis Charalampopoulos , Manal Mohamed , Jakub Radoszewski , Wojciech Rytter , Tomasz Waleń , Wiktor Zuba

Given a set of finite words, the Overlap Graph (OG) is a complete weighted digraph where each word is a node and where the weight of an arc equals the length of the longest overlap of one word onto the other (Overlap is an asymmetric…

Data Structures and Algorithms · Computer Science 2021-11-18 Bastien Cazaux , Eric Rivals

Solving time-harmonic wave propagation problems in the frequency domain and within heterogeneous media brings many mathematical and computational challenges, especially in the high frequency regime. We will focus here on computational…

Numerical Analysis · Mathematics 2021-09-01 Niall Bootland , Victorita Dolean , Pierre Jolivet , Pierre-Henri Tournier

Given in the plane a set of points and a set of halfplanes, we consider the problem of computing a smallest subset of halfplanes whose union covers all points. In this paper, we present an $O(n^{4/3}\log^{5/3}n\log^{O(1)}\log n)$-time…

Computational Geometry · Computer Science 2024-02-27 Haitao Wang , Jie Xue

We consider the problem of decompressing the Lempel--Ziv 77 representation of a string $S$ of length $n$ using a working space as close as possible to the size $z$ of the input. The folklore solution for the problem runs in $O(n)$ time but…

Data Structures and Algorithms · Computer Science 2019-11-05 Philip Bille , Mikko Berggren Ettienne , Travis Gagie , Inge Li Gørtz , Nicola Prezza

Two decades ago, a breakthrough in indexing string collections made it possible to represent them within their compressed space while at the same time offering indexed search functionalities. As this new technology permeated through…

Data Structures and Algorithms · Computer Science 2022-11-28 Gonzalo Navarro

We present a new algorithm for computing $m$-th roots over the finite field $\F_q$, where $q = p^n$, with $p$ a prime, and $m$ any positive integer. In the particular case $m=2$, the cost of the new algorithm is an expected $O(\M(n)\log (p)…

Data Structures and Algorithms · Computer Science 2011-10-20 Javad Doliskani , Eric Schost

In multimedia, text or bioinformatics databases, applications query sequences of n consecutive symbols called n-grams. Estimating the number of distinct n-grams is a view-size estimation problem. While view sizes can be estimated by…

Databases · Computer Science 2014-02-05 Daniel Lemire , Owen Kaser