Services & Resources / Wolfram Forums / MathGroup Archive

MathGroup Archive 2010

[Date Index] [Thread Index] [Author Index]

Search the Archive

matrix equation

  • To: mathgroup at
  • Subject: [mg109590] matrix equation
  • From: "Conlon, Paul" <Paul.Conlon at>
  • Date: Fri, 7 May 2010 06:28:48 -0400 (EDT)

Hi & thanks.

Here is my problem:

Similarity matrix equation:    A . B   == ==   B . C

If I have A and C, how do I determine B? I've looked at Solve and
eigenvalues, etc. and have limited success with Solve (can accurately
get a several of the matrix element, but not all. Eg  seems I can get
sort of  parametric response when I put in B where I have the elements
....{{m11, m12, ...}, {m21, m22,....},  ...} ).

Surely there is a solution because I can create A,B,C that work. But
sometimes I get elements that are the trivial solution (zeroes). Also,
this is for a real world app, so the elements are real. I looked at
Solve, SolveAlways, FindInstance and the other recommended fns. If it is
parametric, interesting, but since I get some correct values from
real-world (vs real - ha)  matrices I am dealing with that seems less



  • Prev by Date: Giving several functions the same argument
  • Next by Date: Re: NDSolve backward in time
  • Previous by thread: Re: Giving several functions the same argument
  • Next by thread: Re: matrix equation