Talk:Kronecker delta

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Mathematics rating:	Start Class	High Priority	Field: Basics
Please update this rating as the article progresses, or if the rating is inaccurate. Click to show/hide comments. Please add to or update the comments to suggest improvements to the article. --Cronholm144 03:30, 16 June 2007 (UTC)

To claim as the article does that the Kronecker delta is a discrete analogue of the Dirac delta is very funny. The Dirac delta came afterwards, was named delta by analogy with Kronecker's and is not even an integral kernel, while the Kronecker delta is a bona fide matrix. — Miguel 22:12, 2004 Nov 21 (UTC)

There's another definition of the generalized Kronecker delta that is defined by the sign of the permutation that maps the contravariant indices to the covariant ones. It's equal to and sometimes defined by a determinant of regular Kronecker deltas. Do a search on Planetmath for more info. Jason Quinn 19:57, 11 Mar 2005 (UTC)

[edit] Unit Impulse Function

The unit impulse function is defined as a combination of two formulas. One defining where the function is zero:

And one stating that the entire integral must be equal to one:

Maybe it should be pointed out that the unit impulse is the same one as the Dirac delta. Anyway I would move the whole treatment of the unit impulse function to the appropriate article (instead of giving overhere two definitions of this other mathematical object). Andy 22:36, 20 September 2006 (UTC)

--Bob K 13:51, 21 September 2006 (UTC)