Re: matrix times a vector

*To*: mathgroup at smc.vnet.net*Subject*: [mg49058] Re: matrix times a vector*From*: Paul Abbott <paul at physics.uwa.edu.au>*Date*: Tue, 29 Jun 2004 04:50:52 -0400 (EDT)*Organization*: The University of Western Australia*References*: <cbokn1$4bl$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

In article <cbokn1$4bl$1 at smc.vnet.net>, David Salomon <david.salomon at csun.edu> wrote: > Question: > > The input {{a,b}, {c,d}}.{x,y} generates the output {a x+b y,c > x+d y}. > > How can I get the output x{a,b}+y{c,d} ? By direct multiplication (note that . has been deleted): {{a,b}, {c,d}} {x,y} > This is a special case of lists with two elements. How > can I extend this computation in an elegant way to lists > with N elements? This works with n elements: {{a, b, c}, {c, d, e}, {e, f, g}, {f, g, h}} {x, y, t, u} Cheers, Paul -- Paul Abbott Phone: +61 8 9380 2734 School of Physics, M013 Fax: +61 8 9380 1014 The University of Western Australia (CRICOS Provider No 00126G) 35 Stirling Highway Crawley WA 6009 mailto:paul at physics.uwa.edu.au AUSTRALIA http://physics.uwa.edu.au/~paul