Acknowledgements for _Linear Algebra_ by Jim Hefferon This document was started 2001-Oct-08, in response to the help I've been offered by various people from the web. To everyone who wrote and contributed, Thank you! ====================================================== General: I'd like to thank Saint Michael's College, the Math Department at Saint Michael's College, including George Ashline, Rick Cleary, and Lloyd Simons for using drafts of this book in class. Their feedback was very helpful. In particular, GA pointed out many typos. 2001-Oct-08 Guillaume Belanger, typo Gabriel Gellen, some typos Ken Yocom and John Iverson, typos, corrections 2002-Dec-31 Clarke Stone, typo Javed Iqbal, PDF misbehavior 2003-Feb-26 Bob Hayden, many corrections in the Leontief topic Brandon Barker, typo Hynek Hanke, typo Jon Thurmond, typo Sheldon Robinson, typo Jack Moffitt, typo 2003-May-13 Jack Moffitt, typos 2008-July-20 Harry (ypsilonj at domain gmail.com), typos Einar Bjarki Gunnarsson, corrections to answers Clint Ward, correction to exercise Yufei Chen, corrections to exercises Bernd Losert, many corrections and clarifications of exercises. Dinko Tenev, correction to an exercise Tom Fitzhenry, correction to an exercise Oliver Ferrari, correction to an exercise Dan Boswel, correction to an exercise Pedro Arias Castanedo, correction to preface Ali Ghodsi, several very helpful corrections to text body 2011-Jan-01 Christopher Kirkos Suggestion to date PDF's Romain Iehl answer to exercise correction Goran Topic exercise suggestion Raphaele Herbin misplaced reference Keith Russell correction to discussion in Method of Powers David Garcia Quintas corrections to exercise and text body Lennon Conson correction to exercise answer Ali Ghodsi corrections to two diagrams Wlodek Bryc correction to exercise answer, misspelling of Schwarz Jacob Schlather suggestions about linear recurrences Jim Schmitz corrections to exercise answers Gideon Mann correction to formula Pavel Dudrenov correction to computer code Mike Bibby comment about an example Adrian Suarez comment about the presentation Fred Maranhao correction of exercise Barrett Walls for a review with many helpful comments and corrections Barbara Glass for a review also with many helpful comments and corrections Iason Irusodimos for the review also with helpful comments and corrections Stephen Solomon of Eleven Learning arrangement of the reviews 2011-Dec-06 Arthur A Nardiello correction of discussion of determinant function Gurpreet Sidhu clarification of linear independence example Brian Scholl correction to exercise answers, and examples in Jordan Form chapter Naveen Goswamy correction to example of CAS Allen Rogers correction to a subtle point in an exercise on linear independence Todd Iverson pointer to a fine proof of the uniqueness of reduced echelon form Robert H Lewis remarks about the definition of determinant Rick Cleary slick answer to an exercise Jane Holsapple Long correction to populations topic Colin Fraizer typos in appendix 2012-Jan-31 Marco Daniel for help with an mdframed issue. CJ Fearnley corrections for projective geometry topic 2012-Mar-28 George Ashline for schedule of sections covered Lindsay Meyer for help with soem exercises in the Vector Spaces chapter 2012-Apr-11 Dan Velleman several suggestions, including about using multisets in defn of linear independence 2012-Jun-13 David Guichard corrections and some helpful discussions 2012-Oct-01 DG formatting of some links in jhanswers not right 2012-Oct-20 Ken Shrirriff addition to introduction of determinant function. 2013-Jan-01 Itamar Stein hole in proof of Jordan form David Guichard several corrections throughout text Troy J. Jasso hyperref'ed links in index wrong (I couldn't figure out how to correct; dropped links) 2013-Dec-13 J Alacqua Change - to + in introduction to Triangle Inequality Jeff Haag, and student Error in answer to eigenspace exercise Felix Bier Error in Matrix Representation answer Joakim Fremstad typo in example of representation of vector wrt basis Vinícius dos Santos Oliveira Typo in slide def of std basis Diego Alexander Huerfano Villalba Correction to exercise on representation wrt a basis, correction to exercise on sum of entires of each row Mike Brown Suggestion about describing US coins "pennies", etc., for non-US audiences Mana Borwornpadungkitti Missing case in answer to Reduced Echelon Form exercise Jad Nohra, Tom Lahore, Lopatin Vladimir Many corrections, large and small. 2014-Jan-08 Mana Borwornpadungkitti Correction to exercise answer. 2014-Feb-21 Mana Borwornpadungkitti Number of corrections to homogeom. 2014-Apr-16 Fred Richman Number of suggestions and corrections, including terminology. 2014-Nov-24 Mana Borwornpadungkitti Number of careful typo corrections. Ronald Herr Correction to answers of Networks, question 2. Chris Thron Large number of corrections and substantial comments. Fixed subtle error in Three.II.2.31. Chris Atkinson Correction to partition example in appendix, typo in Three.3.2.6. Dan Drake Very helpful discussion of a better example of the need for the set/multiset distinction in the definition of linear independence. Darren Wick Many corrections to slides. 2015-Jan-06 Gario Gjorgjevski Typo in Schur's Triangularization Lemma. 2015-Jan-14 Arthur Kock Unclear exercise in Isomorphism section. 2016-May-31 Dave Hein Clarify question and answer for exercise 1.28 in One.I. Maria H Misspelling after definition of Vector Space Deann Leoni Corrected answer to exercise in vs2. Vinícius dos Santos Oliveira Typo. Jeff Herlitz Correction to answer in One.III. Eric P. Morrill Comment on Exercise in One.I. Karl-Dieter Crisman Large number of corrections, including to mathematical material, not only typos, and a number of very helpful suggestions. Joe Zyburt Two errors in nullspace chains in Nilpotence section. Darij Grinberg Corrections around Cayley-Hamilton. Fred Davis, via David Joyner, many questions with answers for question bank. William Karstens for much help with the Topic on Coupled Pendula. 2016-Aug-20 Christelle Vincent Add slides that use handout option. 2016-Nov-23 Darij Grinberg Many typos. Thoughtful suggestions on a couple of items. David Guichard Many typos and suggestions. Mitch Rothstein Exercise error, and proof suggestion. James Moore Typo. Richard Satterfield Thought-provoking report about free variables. Christopher Thron Incorrect exercise in voting Topic. Poorly worded exercises. David Joyner, David Ruth Exercise answer. 2016-Dec-30 Dylan Frese Matrix column incorrect in example. Andrew Misseldine Number of corrections from students, many answers. 2019-Jul-02 Steve Nicholson (GitLab) Typo in preface. Darij Grinberg (GitLab) Improvements to proof of Chio's Theorem. 2019-Aug-05 Mitch Rothstein Prove all bases have same size by calculation on coords (Changed slides to do this but book retains Exchange Lemma.) Darij Grinberg More typos, and a number of thoughtful suggestions. Improvement in discussion of linear relationships. Andrew Misseldine A number of corrections to solutions. Marcus Christie Correct an exercise on the Geometry of Determinants. Pooya Taherkhani Suggestion about format for printed books. M. Andoor Correction in Changing Map Representations section. Arun Sagar Many helpful comments, and corrections to a number of map solutions. Joe Laszlo Exercise answer, One.I. Clayton Cafiero Missing \vec's in Two.II. John Calabrese Exercise statement correction in Three.I. Yair Kubi Wording correction in One.I. Vincent Porras Answer correction, One.III. Maximiliano Redigonda Correction to answer Three.VI. Phillip Lestmann Correction to exercises in Stable Populations. Clayton Cafiero Exercise answer correction in Five.II. Maximiliano Redigonda Many helpful corrections to exercise answers. Emmanuel Charpentier Improve answer in One.I. William Gore Correct an example in Five.IV. Michal Ramos Improve an exercise answer in Two.III, and correction to development of matrix multiplication. Teresa Mabbutt Correction to exercise answer in Three.IV. Pooya Taherkhani Correction to Two.I. Andrew Stimpson Correction to definition of t-string. Brian Lee Correction in Three.VI. Bill Norton Answer correction in One.I. Rick Cleary Question on span. Park Young Ho Prompt to modify wording in Four.I. Tim Zhi, Mild Thamparanon Alter misleading wording of answer in Three.IV. Leigh Noble Correction to answers in Three.V and Four.II. Rick Cleary Correction to page rank description. Andrew Peak Comments on Diagonalizability example. Larry Dodd Typo in Vector Space introduction. Chris Harding Corrections to homework exercise in Chapter One. A number of other well-spotted points. Evan Wallace Correction to figure in One.II. Nathaniel Schenker A large number of excellent comments and corrections. Wolf Holzmann Write-up of proof of Jordan form existence. Elmir Jagudin Typo in exercise. Wlodek Bryc Extensive an helpful comments on compiling under Windows (this is pre-latexmk; I switched to try to make things better). Shishir Agrawal (and Michael Bennett) Several corrections in Two and Three. Joseph O'Brien Correction to t-string basis definition. Bradley J Ballinger Comment about wording of vector space definition. Brett Presnell Typo in slide five_i. John W. Hoggard Slide compilation. 2020-Mar-09 Tirthankar Mazumder Couple of typos. 2020-Jun-08 Luis Lozano Change superscript in lab. 2020-Sep-30 Keon Moradi Typo in vector entry. 2021-Oct-04 John Hoggard Slides not coming out in three versions. Joseph O'Brien Add comment in jc3 about maximality of strings in basis. Christopher A Ibarra Exercise answer error. Tirthankar Mazumder For lab, Python3 has no sys.maxint. Rick Cleary Correction to exercise wording, correction to another's answer. Mervyn Brumbach Correction to exercise wording, and to another's answer. Carson Hesterman Correction to exercise answer. Chris Pil Correction to exercise answer. Clint Givens Correction to exercise wording. Sasha Lopoukhine Correction to wording in representation of a vector. Stefan Landau Typo in exercise. Alexander M Pappas-McAllister Correction to exercise answer. Tyrone Yan Correction to one of the ugly results about linear independence. Vineeth Thota Error in exercise answer. Jan W B Baltussen Typos on Jordan form section. Jan W B Baltussen More typos, and correction to example. Logan MacNeil Correction to linear independence example. Kaung Thu Excellent correction to a tricky point in the proof that every nilpotent transformation has an associated t-string basis. Lance Decker Correction to exercise answer. Paolo Carlini Typo on home page. Dennis Suratna Typo on Gram-Scmidt diagram. Elliot Roynon Correction to exercise answer, where that same error was in a number of nearby exercises. Andrzej Fiolek Suggestion about induction argument that Gauss's method works. Samuel Wilson and Ashton Lorne Correction to exercise answer. 2021-November-09 Mark Mills Link error on hefferon.net.