{"title":"Positive definiteness of Hadamard exponentials and Hadamard inverses","authors":"Takashi Sano","doi":"10.1007/s11117-024-01070-3","DOIUrl":null,"url":null,"abstract":"<p>Let <i>A</i> be a positive semidefinite matrix. It is known that the Hadamard exponential of <i>A</i> is positive semidefinite; it is positive definite if and only if no two columns of <i>A</i> are identical. We give an alternative proof of the latter part with an application to Hadamard inverses.</p>","PeriodicalId":54596,"journal":{"name":"Positivity","volume":"28 1","pages":""},"PeriodicalIF":0.8000,"publicationDate":"2024-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Positivity","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1007/s11117-024-01070-3","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
Abstract
Let A be a positive semidefinite matrix. It is known that the Hadamard exponential of A is positive semidefinite; it is positive definite if and only if no two columns of A are identical. We give an alternative proof of the latter part with an application to Hadamard inverses.
期刊介绍:
The purpose of Positivity is to provide an outlet for high quality original research in all areas of analysis and its applications to other disciplines having a clear and substantive link to the general theme of positivity. Specifically, articles that illustrate applications of positivity to other disciplines - including but not limited to - economics, engineering, life sciences, physics and statistical decision theory are welcome.
The scope of Positivity is to publish original papers in all areas of mathematics and its applications that are influenced by positivity concepts.