Re: Vector operations,

*To*: mathgroup at smc.vnet.net*Subject*: [mg70019] Re: [mg69993] Vector operations,*From*: "Adriano Pascoletti" <pascolet at dimi.uniud.it>*Date*: Sat, 30 Sep 2006 05:12:54 -0400 (EDT)

Something like this? L = {{1/2, 1/2}, {1, 0}, {0, 1}, {0, 0}}; Transpose[RotationMatrix2D[t].Transpose[L]] yields {{Cos[t]/2 + Sin[t]/2, Cos[t]/2 - Sin[t]/2}, {Cos[t], -Sin[t]}, {Sin[t], Cos[t]}, {0, 0}} Adriano Pascoletti mickey wrote .. > > Hi, > > I have a list of vectors such as > > {{1/2, 1/2}, {1, 0}, {0, 1}, {0, 0}} > > I want to rotate them all by the same angle. Right now, what I do is > multiply each by RotationMatrix2D[t] and iterate over the list. Is there > a more efficient way to do this? > > Thanks, > -M >