MathGroup Archive 2006

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

Search the Archive

Re: problem with Quaternion polynomial root solver

  • To: mathgroup at smc.vnet.net
  • Subject: [mg68265] Re: problem with Quaternion polynomial root solver
  • From: Roger Bagula <rlbagula at sbcglobal.net>
  • Date: Mon, 31 Jul 2006 03:45:21 -0400 (EDT)
  • References: <eahtq5$p0b$1@smc.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

I tried using the built in to do the multiplication steps.
I've come to the conclusion that
for odd quaternions ,cubes =>
q.(q.q) and (q.q).q
there are two distinct polynomials,
but for even powers of q there is only one result.
Holding t constant I looked at a Pisot like root structure as a 3d implict
and there are multi-surface intersections that produce distinct sets of 
roots
in these equations.
I'm no closer to finding a definitive Quaternion Pisot.

Mathematica:
\!\(<< Algebra`Quaternions`\n
  q = Quaternion[t, x, y, z]\n
  q2 = ExpandAll[q ** q]\n
  q3 = \((q ** q)\) ** q\n
  FullSimplify[q3 - q2 - q - Quaternion[1, 0, 0, 0]]\n
  NSolve[{\(-1\) +
    x\^2 + y\^2 + z\^2 + t\ \((\(-1\) + \((\(-1\) + t)\)\ t - 3\ x\^2 - 3\
    y\^2 - 3\ z\^2)\) == 0, \(-
      x\)\ \((1 + \((2 - 3\ t)\)\ t + x\^2 + y\^2 + z\^2)\) ==
  0, \(-y\)\ \((
    1 + \((2 - 3\ t)\)\ t + x\^2 + y\^2 + z\^2)\) ==
           0, \(-z\)\ \((1 + \((
              2 - 3\ t)\)\ t + x\^2 + y\^2 + z\^2)\) == 0}, {t, x, y, z}]\n
  a = Table[{Re[t] - Im[x], Re[x] + Im[t], Re[y] - Im[z], Re[z] + Im[y]} 
/. \
      NSolve[{\(-1\) +
            x\^2 + y\^2 + z\^2 + t\ \((\(-1\) + \((\(-1\) + t)\)\
                t - 3\ x\^2 - 3\ y\^2 - 3\ z\^2)\) == 0, \(-x\)\ \((1 + \((
            2 - 3\ t)\)\ t +
             x\^2 + y\^2 + z\^2)\) == 0, \(-y\)\ \((1 + \((2 - 3\ t)\)\ t +
              x\^2 + y\^2 + z\^2)\) == 0, \(-z\)\ \((1 + \((2 - 3\ t)\)\ t +
             x\^2 + y\^2 + z\^2)\) == 0}, {t, x, y, z}], {n, 1, 6}]\n
  b = Table[Sqrt[\((Re[t] - Im[
            x])\)^2 + \((Re[x] + Im[t])\)^2 + \((Re[y] - Im[z])\)^2 + \
\((Re[z] + Im[y])\)^2] /. \ NSolve[{\(-1\) + x\^2 + y\^2 + z\^2 +
                t\ \((\(-1\) + \((\(-1\) + t)\)\ t - 3\
                    x\^2 - 3\ y\^2 - 3\
                          z\^2)\) == 0, \(-x\)\ \((1 + \((2 - 3\
                      t)\)\ t + x\^2 + y\^2 +
                      z\^2)\) == 0, \(-y\)\ \((1 + \((2 - 3\ t)\)\ t +
               x\^2 + y\^2 + z\^2)\) ==
                  0, \(-z\)\ \((1 + \((2 - 3\ t)\)\ t + x\^2 +
                    y\^2 + z\^2)\) == 0}, {t, x, y, z}], {n, 1, 6}]\)

>
>  
>


  • Prev by Date: Re: RE: Log Function
  • Next by Date: Re: Re: Finding the Number of Pythagorean Triples below a bound
  • Previous by thread: problem with Quaternion polynomial root solver
  • Next by thread: x=2;Composition[f,FindMinimum][x+1,{x,a}]