Comments | sang_et_mort: (без темы)

sang_et_mort

(Untitled)

Nov 08, 2005 00:12

philosophy is not a toy!

Comments 4

So ya wanna know why matrix multiplication is as it is? drakvl December 6 2005, 21:15:36 UTC

In algebra, matrices are a useful way of representing linear transformations between vector spaces. If we have two transformations, and we want to compose them, it is matrix multiplication which provides the representative matrix of the new transformation.

Re: So ya wanna know why matrix multiplication is as it is? sang_et_mort December 10 2005, 05:00:44 UTC

okay, but then why do we call it multiplication? is what is really going on a generalization of what happens when two scalars multiply?

Re: So ya wanna know why matrix multiplication is as it is? drakvl December 16 2005, 21:33:47 UTC

Hmm. Well, consider multiplication and addition on the integers. Addition has an inverse operation -- subtraction. (In this case, multiplication doesn't: for instance, 5 and 2 are integers, but 5/2) is not.) Also, addition has an identity element: 0. (In this case, multiplication does, too: 1.) Also, there's the distributive property, and addition is commutative. These properties make integers, with integer multiplication and addition, into a mathematical object called a ring ( ... )

Re: So ya wanna know why matrix multiplication is as it is? sang_et_mort December 18 2005, 02:41:24 UTC

ah, so there is more structure to it that i wasn't aware of. at its heart it's still all constructed, though wisely so.

heh, i need to work on buying a gamecube. i'm waiting till the twilight princess comes out. i hope there's a price drop. i heard double dash was great too.