Re: How to mutiply a 3x1 and 1x3 vector

*To*: mathgroup at smc.vnet.net*Subject*: [mg3092] Re: How to mutiply a 3x1 and 1x3 vector*From*: wagner at bullwinkle.cs.Colorado.EDU (Dave Wagner)*Date*: Wed, 31 Jan 1996 03:04:03 -0500*Organization*: University of Colorado, Boulder*Sender*: owner-wri-mathgroup at wri.com

In article <4ekes6$6gj at dragonfly.wri.com>, Stephen Nichols <snichols at onramp.net> wrote: > >Hi, > >I have another question that I thought would be simple to to in Mathematica. >I have two vectors A={1,2,3} and B={3,4,5}. How do I multiple them together >to get a 3x3 matrix. A . B gives me a scalar result. Mma seems to always >treat the first one as a row vector and the second as a column vector. I >need it to do the opposite. Treat the first as a column vector and the second >as a row vector. Any ideas? Express your column vector as a 3x1 matrix, and your row vector as a 1x3 matrix: In[1]:= {{1},{2},{3}}.{{3,4,5}} Out[1]= {{3, 4, 5}, {6, 8, 10}, {9, 12, 15}} Dave Wagner Principia Consulting (303) 786-8371 dbwagner at princon.com http://www.princon.com/princon ==== [MESSAGE SEPARATOR] ====