(%i2) gfactor(%i*k^4 -2*k^3 -2*%i*k^2+2*k+%i);
(%o2) %i*(k-1)*(k+1)*(k+%i)^2
See ?gfactor
HTH
Volker van Nek
Michel Talon schrieb:
> Hello,
>
> maxima has difficulties factoring polynomials on the complex field.
> As an example, compare the following maple and maxima computation:
>
> niobe% maple
> |\^/| Maple 9 (IBM INTEL LINUX)
> ._|\| |/|_. Copyright (c) Maplesoft, a division of Waterloo Maple Inc.
> 2003
> \ MAPLE / All rights reserved. Maple is a trademark of
> <____ ____> Waterloo Maple Inc.
> | Type ? for help.
>
>> factor(I*k^4 -2*k^3 -2*I*k^2+2*k+I);
>>
> 2
> (k - 1) (k + 1) (k + I) I
>
>
>> quit
>>
> bytes used=978068, alloc=851812, time=0.05
>
>
> niobe% maxima
> (%i1) algebraic:true;
> (%o1) true
> (%i2) factor(%i*k^4 -2*k^3 -2*%i*k^2+2*k+%i);
> 2
> (%o2) (k - 1) (k + 1) (%i k - 2 k - %i)
> (%i3) factor(%i*k^4 -2*k^3 -2*%i*k^2+2*k+%i,b^2+1);
> 2
> (%o3) %i (k - 1) (k + 1) (k + %i)
>
> Note that it is necessary to specify that the computation is in the field of
> b^2+1 to get the answer. Moreover in many cases, b is returned in place
> of %i and many simplifications are missed.
>
> Is there any way to get more efficient computations?
>
> Thanks you very much
>
>