On 24 Jul 2011, at 19:19, KC wrote:

...

A lot of math books use "+" or "x" enclosed in a circle to indicate that the usual meaning of "+" nor "x" is intended for the meaning of the binary operation.

Er no. Both symbols have extremely precise meanings. $\oplus$ is the

On 7/24/11 2:29 PM, Julian Porter wrote: direct sum of two modules and $\otimes$ is their tensor product. Well, they mean that if you're off in module/vector land; but they don't mean that everywhere. Another place they're used frequently is for semirings: with $\oplus$ the associative monoid and $\otimes$ the other monoid. While the tourism board for semirings is less well funded than the one for vectors, it's a beautiful locale with rich history. Natural language processing, graph theory, Boolean algebras, and related logics are nothing to scoff at. -- Live well, ~wren