Re: Matrices as operators

*To*: mathgroup at smc.vnet.net*Subject*: [mg123018] Re: Matrices as operators*From*: Bob Hanlon <hanlonr357 at gmail.com>*Date*: Mon, 21 Nov 2011 04:24:35 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <201111201034.FAA01071@smc.vnet.net>

Define a function rMatrix = {{Cos[#], -Sin[#]}, {Sin[#], Cos[#]}} &; rMatrix[t] {{Cos[t], -Sin[t]}, {Sin[t], Cos[t]}} or just use the built-in function RotationMatrix[t] {{Cos[t], -Sin[t]}, {Sin[t], Cos[t]}} % == %% True Bob Hanlon On Sun, Nov 20, 2011 at 5:34 AM, Chris Young <cy56 at comcast.net> wrote: > I'd like to be able to abbreviate matrices such as rotation matrices so > that I don't have to repeat the argument. This way I can pass in more > complicated arguments and it also shows the structure of the > transformation more clearly. > > Through[( { > {Cos, -Sin}, > {Sin, Cos} > } )[=E8]] > > will get me partway there: > > Out: {{Cos, -Sin}[=E8], {Sin, Cos}[=E8]} > > I have to apply Thread and Through again to finally get what I want: > > In: Thread[Through[{{Cos, -Sin}[=E8], {Sin, Cos}[=E8]}]] > > Out: {{Cos[=E8], (-Sin)[=E8]}, {Sin[=E8], Cos[=E8]}} > > Is there a shortcut way to do this all in one step? > > Thanks very much for any help. > > Chris Young > cy56 at comcast.net >

**References**:**Matrices as operators***From:*Chris Young <cy56@comcast.net>