Property of TransformationFunction
- To: mathgroup at smc.vnet.net
- Subject: [mg79127] Property of TransformationFunction
- From: "David Park" <djmpark at comcast.net>
- Date: Thu, 19 Jul 2007 03:32:02 -0400 (EDT)
TransformationFunction has what seems to me like a useful but strange attribute. TransformationFunctions operate on vectors. However, if given a list of vectors, that is a matrix, then it will operate on the individual vectors in the list. It is a little like being Listable but only for lists of vectors. I wondered if there are any other functions that behave in this manner? Although the documentation does not seem to explicity describe this behavior, it is illustrated in the documentation for ReflectionTransform under Scope. rt = ReflectionTransform[{u, v, w}] // Simplify[#, {{u, v, w} \[Element] Reals, u^2 + v^2 + w^2 == 1}] & givining a TransformationFunction. Normally it would operate on a vector such as rt@{x, y, z} But the documentation has it operating on a list of vectors: (Showing that vectors in the reflection plane are unchanged) NullSpace[{{u, v, w}}] rt@% // Simplify -- David Park djmpark at comcast.net http://home.comcast.net/~djmpark/