User talk:Gbgustafson

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Cheers! prime mover (talk) 08:21, 27 September 2019 (EDT)

6 October 2019
Edited the current proof of the Banach Fixed Point Theorem. Not sure how new theorems are submitted. First attempt was to edit an existing proof. I proceeded by example from other pages. It took about a week to get used to the House Style, which uses macros and environments similar to my own used for books, monographs and papers.

14 October 2019
R.Gow in the Irish Math Bulletin 28 (1992), p 45, uses the term "Vandermonde matrix" as the transpose of the Vandermonde matrix as currently defined in ProofWiki and Wikipedia. I also saw a difference in definitions for interpolation problems, especially Wikipedia.


 * There are enough variants of the Vandermonde matrix (is "Vandemonde" a spello of Gow's?) that I wonder whether we're due for a refactoring so as to explicitly document them all and explain the nuances. Admittedly the differences are more-or-less trivial (1-based vs x-based, transposes of each) but may be profitable for a newcomer. Thoughts? --prime mover (talk) 10:08, 14 October 2019 (EDT)

Missing "r" in Vandermonde was my typo, a cheap keyboard feature. The nuances are already covered in what exists on the page. I vote NO for explaining nuances.

Alexander C. Atiken (1939) cites (page 50) Vandermonde (1771) as the founder of notation and calculus for determinants, but uses the term "alternant" for what is defined in ProofWiki as a "Vandermonde determinant." Aitken's source for history is Muir's volumes on the history of determinants. I will add a reference to alternants and to Aitken's book. Aitken never used any form of Vandermonde's matrix except the first form on the ProofWiki page, ones in column 1, using term "alternant", e.g., A(0123) in his notation.