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We show how eigenvalue problems can be solved in this setting by QR reduction to square matrix generalized eigenvalue problems. The method applies equally in the limit \u201c<jats:inline-formula><jats:alternatives><jats:tex-math>$m=\\infty $<\/jats:tex-math><mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\">\n                  <mml:mi>m<\/mml:mi>\n                  <mml:mo>=<\/mml:mo>\n                  <mml:mi>\u221e<\/mml:mi>\n                <\/mml:math><\/jats:alternatives><\/jats:inline-formula>\u201d of eigenvalue problems for quasimatrices. Numerical examples are presented as well as pointers to related literature.<\/jats:p>","DOI":"10.1007\/s10444-022-09994-8","type":"journal-article","created":{"date-parts":[[2022,11,16]],"date-time":"2022-11-16T09:03:37Z","timestamp":1668589417000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Rectangular eigenvalue problems"],"prefix":"10.1007","volume":"48","author":[{"given":"Behnam","family":"Hashemi","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuji","family":"Nakatsukasa","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2504-1709","authenticated-orcid":false,"given":"Lloyd N.","family":"Trefethen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2022,11,16]]},"reference":[{"key":"9994_CR1","doi-asserted-by":"publisher","first-page":"423","DOI":"10.1137\/16M1065975","volume":"59","author":"JL Aurentz","year":"2017","unstructured":"Aurentz, J.L., Trefethen, L.N.: Block operators and spectral discretizations. 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