Talk:Trace (linear algebra)
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I do not think that the article title "Trace (matrix)" is any clearer than "Trace of a matrix". In fact, quite the opposite.
Wikipedia articles are about concepts, not about words. This is not about the word "trace" in the context of matrix theory (in which case it should properly be called "Trace (matrix theory)" or "Trace (linear algebra)"), but it is about the concept "Trace of a matrix", which is a perfectly self-explanatory headline of the article. AxelBoldt 23:10 Jan 31, 2003 (UTC)
I would like to see 2 things: Brief paragraph on the importace of the trace, and an intoative proof of the main feature (is it main?) tr(AB) = tr(BA). thanks
- I agree that this article should be renamed. Mainly because the concept of the trace is more general that that of a matrix. In other words there is a class of linear transformations for which the trace makes sense which are not matrices. move the article to Trace -Lethe | Talk
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[edit] Trace of matrix products
I would like to suggest a change regarding the trace of the product of several (>2) matrices. Specifically the part beginning "If A, B, and C are square...". The phrase "all permutations" is, strictly speaking, not correct. The last three terms in the chained equality, while looking like general permutations, are transposes of the first three with the transpose marks omitted due to symmetry. My motivation for the change is that if more than three matrices are involved only the cyclic permutation may be used to reorder the matrices. Transposing with symmetry assumed will make more (apparent) permutations possible, but not all posible permutations. My quick and dirty suggestion is to delete the entire paragraph along with the chained equality. It could be fixed but it is just a special case involving the previously discussed cyclic permutation and transpose along with the symmetry condition. Doggit 17:19, 10 August 2006 (UTC)
[edit] Direct Link
I set the link from spur to this article. --Kajaktiger 16:47, 4 November 2006 (UTC)
[edit] Derivatives
Don't revert back to d Tr = I. This is not true. There is a vectorisation operator present if you must present the information in this form. The peterson & pederson seem to have dropped this when they copy pasted from brookes.
Just goes to show what sort of crap you can find on the internet. —The preceding unsigned comment was added by 150.203.45.188 (talk) 09:35, 5 December 2006 (UTC).
[edit] Inner product
I think that following 
, it should be mentioned that * B is the conjugate transpose of B. 131.130.90.152 10:36, 22 January 2007 (UTC)
