{"title":"A block upper triangular splitting method for solving block three-by-three linear systems arising from the large indefinite least squares problem","authors":"Jun Li , Kailiang Xin , Lingsheng Meng","doi":"10.1016/j.amc.2025.129546","DOIUrl":"10.1016/j.amc.2025.129546","url":null,"abstract":"<div><div>In this research, we mainly utilize the stationary iteration method in conjunction with Krylov subspace techniques, such as GMRES, to tackle the large indefinite least squares problem. To accomplish this, the normal equation of the large indefinite least squares problem is firstly transformed into the sparse block three-by-three linear systems with non-singular diagonal blocks, then a block upper triangular matrix splitting of the coefficient matrix of the block three-by-three linear systems is given, the splitting not only produces the stationary iteration method, but also naturally derives a preconditioner, which can be used within GMRES method to solve the block linear systems. Thereafter, it is proved theoretically that the iteration method has unconditional convergence. Furthermore, the theory also shows that all the eigenvalues of the preconditioned matrix are real number and located in a positive interval. In the end, numerical results reflect that the theoretical results are correct and the studied methods are also effective.</div></div>","PeriodicalId":55496,"journal":{"name":"Applied Mathematics and Computation","volume":"505 ","pages":"Article 129546"},"PeriodicalIF":3.5,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144105911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yigit Gunsur Elmacioglu , Rory Conlin , Daniel W. Dudt , Dario Panici , Egemen Kolemen
{"title":"ZERNIPAX: A fast and accurate Zernike polynomial calculator in Python","authors":"Yigit Gunsur Elmacioglu , Rory Conlin , Daniel W. Dudt , Dario Panici , Egemen Kolemen","doi":"10.1016/j.amc.2025.129534","DOIUrl":"10.1016/j.amc.2025.129534","url":null,"abstract":"<div><div>Zernike polynomials serve as an orthogonal basis on the unit disc, and have proven to be effective in optics simulations, astrophysics, and more recently in plasma simulations. Unlike Bessel functions, Zernike polynomials are inherently finite and smooth at the disc center (r=0), ensuring continuous differentiability along the axis. This property makes them particularly suitable for simulations, requiring no additional handling at the origin. We developed <span>ZERNIPAX</span>, an open-source Python package capable of utilizing CPU/GPUs, leveraging Google's <span>JAX</span> package and available on GitHub as well as the Python software repository PyPI. Our implementation of the recursion relation between Jacobi polynomials significantly improves computation time compared to alternative methods by use of parallel computing while still performing more accurately for high-mode numbers.</div></div>","PeriodicalId":55496,"journal":{"name":"Applied Mathematics and Computation","volume":"505 ","pages":"Article 129534"},"PeriodicalIF":3.5,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144105910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xuan Li, Jin Su, Jin-Qian Feng, Xiong Lei, Rui-Bo Zhang
{"title":"A hybrid dynamic mode decomposition algorithm combining random and sparsity promoting and its application to viscoelastic flow around circular cylinder","authors":"Xuan Li, Jin Su, Jin-Qian Feng, Xiong Lei, Rui-Bo Zhang","doi":"10.1016/j.amc.2025.129508","DOIUrl":"10.1016/j.amc.2025.129508","url":null,"abstract":"<div><div>Dynamic mode decomposition (DMD) algorithm is widely applied to identify the flow characteristics of fluid dynamic field. However, for high-dimensional viscoelastic fluid systems, DMD might often result in unsatisfactory performance because of its huge computation cost. Therefore, we propose an improved dynamic mode decomposition algorithm, called sparsity promoting randomized dynamic mode decomposition (SP-RDMD). In our method, random projection techniques is firstly used to reduce the computational complexity, and then sparsity promoting is furtherly incorporated to remove the non-critical modes. Then we apply this method to study viscoelastic flow around circular cylinder. The numerical results show that the presented algorithm can effectively identify and extract the low-dimensional dynamic structure of viscoelastic fluid with steady state. Comparing with the traditional DMD, SP-RDMD can not only reconstruct the overall flow pattern of the viscoelastic flow field with fewer modes, but also make the reconstructed viscoelastic flow field show more local details. Moreover, the computational efficiency of SP-RDMD could be improved significantly yet.</div></div>","PeriodicalId":55496,"journal":{"name":"Applied Mathematics and Computation","volume":"505 ","pages":"Article 129508"},"PeriodicalIF":3.5,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144105909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Helena Biščević , Raffaele D'Ambrosio , Stefano Di Giovacchino
{"title":"Contractivity of stochastic θ-methods under non-global Lipschitz conditions","authors":"Helena Biščević , Raffaele D'Ambrosio , Stefano Di Giovacchino","doi":"10.1016/j.amc.2025.129527","DOIUrl":"10.1016/j.amc.2025.129527","url":null,"abstract":"<div><div>The paper is devoted to address the numerical preservation of the exponential mean-square contractive character of the dynamics of stochastic differential equations (SDEs), whose drift and diffusion coefficients are subject to non-global Lipschitz assumptions. The conservative attitude of stochastic <em>θ</em>-methods is analyzed both for Itô and Stratonovich SDEs. The case of systems with linear drift is also analyzed in terms of spectral properties of the coefficient matrix of the drift. Numerical evidence on selected test problems confirms the effectiveness of the approach.</div></div>","PeriodicalId":55496,"journal":{"name":"Applied Mathematics and Computation","volume":"505 ","pages":"Article 129527"},"PeriodicalIF":3.5,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144099817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Partitioning vertices and edges of graphs into connected subgraphs","authors":"Olivier Baudon , Julien Bensmail , Lyn Vayssieres","doi":"10.1016/j.amc.2025.129531","DOIUrl":"10.1016/j.amc.2025.129531","url":null,"abstract":"<div><div>Arbitrarily partitionable (AP) graphs are graphs that can have their vertices partitioned into arbitrarily many parts inducing connected graphs of arbitrary orders. Since their introduction, several aspects of AP graphs have been investigated in literature, including structural and algorithmic aspects, their connections with other fundamental notions of graph theory, and variants of the original notion. Quite recently, an edge version of AP graphs, called arbitrarily edge-partitionable (AEP) graphs have been introduced and studied, with a special focus on their similarities and discrepancies with AP graphs.</div><div>In this work, we introduce and study a total variant of AP graphs, called arbitrarily total-partitionable (ATP) graphs, which essentially stand as a combination of AP and AEP graphs, for some particular notion of connectivity for sets of vertices and edges. We establish results of several natures, which we compare to known, similar results for AP and AEP graphs. In particular, we prove that, although the involved definitions are rather close, being AP, AEP, and/or ATP for a graph does not guarantee it also has the other properties. We also establish that deciding whether a tree can be partitioned in this total way is <span>NP</span>-complete in general, and provide sufficient conditions for ATPness in terms of longest paths. We finally raise directions for further work on the topic.</div></div>","PeriodicalId":55496,"journal":{"name":"Applied Mathematics and Computation","volume":"505 ","pages":"Article 129531"},"PeriodicalIF":3.5,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144090508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A complete solution for maximizing the general Sombor index of chemical trees with given number of pendant vertices","authors":"Sultan Ahmad , Kinkar Chandra Das","doi":"10.1016/j.amc.2025.129532","DOIUrl":"10.1016/j.amc.2025.129532","url":null,"abstract":"<div><div>For a graph <em>G</em>, the general Sombor (<span><math><msub><mrow><mi>SO</mi></mrow><mrow><mi>α</mi></mrow></msub></math></span>) index is defined as:<span><span><span><math><msub><mrow><mi>SO</mi></mrow><mrow><mi>α</mi></mrow></msub><mo>(</mo><mi>G</mi><mo>)</mo><mo>=</mo><munder><mo>∑</mo><mrow><msub><mrow><mi>v</mi></mrow><mrow><mi>i</mi></mrow></msub><msub><mrow><mi>v</mi></mrow><mrow><mi>j</mi></mrow></msub><mo>∈</mo><mi>E</mi><mo>(</mo><mi>G</mi><mo>)</mo></mrow></munder><msup><mrow><mo>(</mo><msubsup><mrow><mi>d</mi></mrow><mrow><mi>i</mi></mrow><mrow><mn>2</mn></mrow></msubsup><mo>+</mo><msubsup><mrow><mi>d</mi></mrow><mrow><mi>j</mi></mrow><mrow><mn>2</mn></mrow></msubsup><mo>)</mo></mrow><mrow><mi>α</mi></mrow></msup><mo>,</mo></math></span></span></span> where <span><math><mi>α</mi><mo>≠</mo><mn>0</mn></math></span> is a real number, <span><math><mi>E</mi><mo>(</mo><mi>G</mi><mo>)</mo></math></span> is the edge set and <span><math><msub><mrow><mi>d</mi></mrow><mrow><mi>i</mi></mrow></msub></math></span> denotes the degree of a vertex <span><math><msub><mrow><mi>v</mi></mrow><mrow><mi>i</mi></mrow></msub></math></span> in <em>G</em>. A chemical tree is a tree in which no vertex has a degree greater than 4, and a pendant vertex is a vertex with degree 1. This paper aims to completely characterize the <em>n</em>− vertex chemical trees with a fixed number of pendant vertices (=<em>p</em>) that maximize the <span><math><msub><mrow><mi>SO</mi></mrow><mrow><mi>α</mi></mrow></msub></math></span> index over <span><math><msub><mrow><mi>α</mi></mrow><mrow><mn>0</mn></mrow></msub><mo><</mo><mi>α</mi><mo><</mo><msub><mrow><mi>α</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span>, where <span><math><msub><mrow><mi>α</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>≈</mo><mn>0.144</mn></math></span> is the unique non-zero root of equation <span><math><mn>4</mn><mo>(</mo><msup><mrow><mn>32</mn></mrow><mrow><mi>α</mi></mrow></msup><mo>−</mo><msup><mrow><mn>25</mn></mrow><mrow><mi>α</mi></mrow></msup><mo>)</mo><mo>+</mo><msup><mrow><mn>8</mn></mrow><mrow><mi>α</mi></mrow></msup><mo>−</mo><msup><mrow><mn>13</mn></mrow><mrow><mi>α</mi></mrow></msup><mo>+</mo><msup><mrow><mn>5</mn></mrow><mrow><mi>α</mi></mrow></msup><mo>−</mo><msup><mrow><mn>10</mn></mrow><mrow><mi>α</mi></mrow></msup><mo>=</mo><mn>0</mn></math></span> and <span><math><msub><mrow><mi>α</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>≈</mo><mn>3.335</mn></math></span> is the unique non-zero solution of equation <span><math><mn>3</mn><mspace></mspace><mo>(</mo><msup><mrow><mn>17</mn></mrow><mrow><mi>α</mi></mrow></msup><mo>−</mo><msup><mrow><mn>10</mn></mrow><mrow><mi>α</mi></mrow></msup><mo>)</mo><mo>+</mo><mn>3</mn><mspace></mspace><msup><mrow><mo>(</mo><mn>20</mn><mo>)</mo></mrow><mrow><mi>α</mi></mrow></msup><mo>−</mo><msup><mrow><mn>13</mn></mrow><mrow><mi>α</mi></mrow></msup><mo>−</mo><mn>2</mn><mspace></mspace><msup><mrow><mo>(</mo><mn>25</mn><mo>)</mo></mrow><mrow><mi","PeriodicalId":55496,"journal":{"name":"Applied Mathematics and Computation","volume":"505 ","pages":"Article 129532"},"PeriodicalIF":3.5,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144090507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Metric dimensions of generalized Sierpiński graphs over squares","authors":"S. Prabhu , T. Jenifer Janany , Sandi Klavžar","doi":"10.1016/j.amc.2025.129528","DOIUrl":"10.1016/j.amc.2025.129528","url":null,"abstract":"<div><div>Metric dimension is a valuable parameter that helps address problems related to network design, localization, and information retrieval by identifying the minimum number of landmarks required to uniquely determine distances between vertices in a graph. Generalized Sierpiński graphs represent a captivating class of fractal-inspired networks that have gained prominence in various scientific disciplines and practical applications. Their fractal nature has also found relevance in antenna design, image compression, and the study of porous materials. The hypercube is a prevalent interconnection network architecture known for its symmetry, vertex transitivity, regularity, recursive structure, high connectedness, and simple routing. Various variations of hypercubes have emerged in literature to meet the demands of practical applications. Sometimes, they are the spanning subgraphs of it. This study examines the generalized Sierpiński graphs over <span><math><msub><mrow><mi>C</mi></mrow><mrow><mn>4</mn></mrow></msub></math></span>, which are spanning subgraphs of hypercubes and determines the metric dimension and their variants. This is in contrast to hypercubes, where these properties are inherently complicated. Along the way, the role of twin vertices in the theory of metric dimensions is further elaborated.</div></div>","PeriodicalId":55496,"journal":{"name":"Applied Mathematics and Computation","volume":"505 ","pages":"Article 129528"},"PeriodicalIF":3.5,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144083972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The impact of heterogeneous preferences on multi-issue repeated social dilemma games with correlated strategy in structured populations","authors":"Ji Quan , Ran Lv , Shengjin Cui , Xianjia Wang","doi":"10.1016/j.amc.2025.129509","DOIUrl":"10.1016/j.amc.2025.129509","url":null,"abstract":"<div><div>Individuals frequently engage in a multitude of concurrent games. Owing to the complexity of the interactions and the inherent diversity in players' preferences, this paper introduces a multi-issue game model tailored for structured populations characterized by heterogeneous preferences. The model incorporates several dimensions of preference diversity, including the relative weight accorded to different games, and the form of preference and distribution patterns within the population. Through numerical experiments, we reveal that structured populations foster cooperation in the context of two-issue repeated social dilemma games. Two predominant preference distribution patterns are compared. The first assumes a random uniform distribution, implying that preferences are distributed evenly across the population. The second is a special distribution, in which players with similar preferences are more likely to form clusters or groups. Our findings underscore that when preferences carry equal weight across the two games, cooperation flourishes most robustly. Furthermore, the binary forms of preference and the excessive variance of preferences in the populations both hinder the emergence and sustainability of cooperative behaviors. Notably, when delving into the impact of preference distributions, we discern that special distributions are less conducive to cooperation compared to their uniform distributions. Overall, this study enriches our comprehension of cooperative phenomena in complex, multi-dimensional gaming scenarios by incorporating heterogeneous preferences.</div></div>","PeriodicalId":55496,"journal":{"name":"Applied Mathematics and Computation","volume":"505 ","pages":"Article 129509"},"PeriodicalIF":3.5,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144083971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Numerical methods of oscillatory Bessel transforms with algebraic and Cauchy singularities","authors":"Yingying Jia, Hongchao Kang","doi":"10.1016/j.amc.2025.129523","DOIUrl":"10.1016/j.amc.2025.129523","url":null,"abstract":"<div><div>This article proposes and analyzes fast and precise numerical methods for calculating the Bessel integral, which exhibits rapid oscillations and includes algebraic and Cauchy singularities. When <span><math><mi>a</mi><mo>></mo><mn>0</mn></math></span>, we utilize the numerical steepest descent method with the Gauss-Laguerre quadrature formula to solve it. If <span><math><mi>a</mi><mo>=</mo><mn>0</mn></math></span>, we partition the integral into two parts, solving each part using the modified Filon-type method and the numerical steepest descent method, respectively. Moreover, the strict error analysis with respect to the frequency parameter <em>ω</em> is provided via a plenty of theoretical analysis. Finally, the efficiency and precision of these proposed methods are validated by numerical examples.</div></div>","PeriodicalId":55496,"journal":{"name":"Applied Mathematics and Computation","volume":"505 ","pages":"Article 129523"},"PeriodicalIF":3.5,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144083974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Local and semilocal analysis of a class of fourth order methods under common set of assumptions","authors":"Ajil Kunnarath, Santhosh George, P. Jidesh","doi":"10.1016/j.amc.2025.129526","DOIUrl":"10.1016/j.amc.2025.129526","url":null,"abstract":"<div><div>This study presents an efficient class of fourth-order iterative methods introduced by Ali Zein (2024) in a more abstract Banach space setting. The Convergence Order of this class is proved by bypassing the Taylor expansion. We use the mean value theorem and relax the differentiability assumptions of the involved function. At the outset, we provide a semilocal analysis, and then, using the results and the same set of assumptions, we study the local convergence. This approach has the advantage that we do not need to use any assumptions on the unknown solution to study the local convergence. This technique can be used to extend the applicability of other methods along the same lines. Examples from both the chemical and the physical sciences are studied to analyze the performance of the class. The dynamics of the class are also studied.</div></div>","PeriodicalId":55496,"journal":{"name":"Applied Mathematics and Computation","volume":"505 ","pages":"Article 129526"},"PeriodicalIF":3.5,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144083973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}