
Re: Another question about Factor
Posted:
Nov 22, 2012 6:31 PM


Dear Dr. M. Abbasi,
Thank you very much for your kindly reply. I wish mathematica give me an express which I can code by Fortran with smallest number of floating operations. For example, if I have:
bb1 = Det[{{1, 1, 1}, {y2, y3, y4}, {z2, z3, z4}}];
the result by mathematica is: y3 z2  y4 z2  y2 z3 + y4 z3 + y2 z4  y3 z4
I wish it output the result like this: z2 (y3y4)  z3 (y2y4) + z4 (y2y3)
What should I do?
Thanks, Tang Laoya
On Thursday, November 22, 2012 11:52:01 PM UTC+8, Nasser M. Abbasi wrote: > On 11/22/2012 9:19 AM, Tang Laoya wrote: > > > Dear all, > > > > > > I need to factor a polynomial express, however, it doesn't work, could anyone help > > >me to take a look at it? > > > > > > > > > > > The code: > > > > > > vv = Det[{{1, 1, 1, 1}, {x1, x2, x3, x4}, {y1, y2, y3, y4}, {z1, z2, > > > z3, z4}}]; > > > > It is order one multivariate polynomial in x_i's, y_i's and z_i's and > > unity coefficients on all the terms. > > > > In[22]:= vv = Det[{{1, 1, 1, 1}, {x1, x2, x3, x4}, {y1, y2, y3, y4}, {z1, z2, z3, z4}}] > > > > Out[22]= x3*y2*z1  x4*y2*z1  x2*y3*z1 + x4*y3*z1 + x2*y4*z1  x3*y4*z1  > > x3*y1*z2 + x4*y1*z2 + x1*y3*z2  x4*y3*z2  x1*y4*z2 + x3*y4*z2 + > > x2*y1*z3  x4*y1*z3  x1*y2*z3 + x4*y2*z3 + x1*y4*z3  > > x2*y4*z3  x2*y1*z4 + x3*y1*z4 + x1*y2*z4  x3*y2*z4  x1*y3*z4 + x2*y3*z4 > > > > In[38]:= PolynomialQ[vv,{x1,x2,x3,x4,y1,y2,y3,y4,z1,z2,z3,4}] > > Out[38]= True > > > > In[35]:= IrreduciblePolynomialQ[vv] > > Out[35]= True > > > > In[36]:= IrreduciblePolynomialQ[vv,Extension>All] > > Out[36]= True > > > > What Factors were you looking for? Tried in Maple also. Same result. > > > > Nasser

