4
1 + y1 + y2 + y3 + y4;
y1 + y1*y2 + y2*y3 + y3*y4 + y4;
y1*y2 + y1*y2*y3 + y2*y3*y4 + y3*y4 + y4*y1;
y1*y2*y3 + y1*y2*y3*y4 + y2*y3*y4 + y3*y4*y1 + y4*y1*y2;
z0**5*y1*y2*y3*y4 - 1;
TITLE : reduced cyclic 5-roots problem
ROOT COUNTS :
total degree : 4! = 24
multi-homogeneous Bezout bound : 24
generalized Bezout bound : 20
based on
{ y1 y2 y3 y4 }
{ y1 y3 }{ y2 y4 }
{ y1 }{ y2 }{ y3 }{ y4 }
{ y1 }{ y2 }{ y3 }{ y4 }
mixed volume : 14
REFERENCES :
See Ioannis Z. Emiris:
`Sparse Elimination and Application in Kinematics'
PhD Thesis, Computer Science, University of California at Berkeley, 1994,
page 25.
yi = zi/z0
This reduced the dimension of the problem by 1 and the mixed volume
drops with 5.
For the original problem,
see G\"oran Bj\"orck and Ralf Fr\"oberg:
`A faster way to count the solutions of inhomogeneous systems
of algebraic equations, with applications to cyclic n-roots',
in J. Symbolic Computation (1991) 12, pp 329--336.
THE SYMMETRY GROUP :
y1 y2 y3 y4
y4 y3 y2 y1
THE GENERATING SOLUTIONS :
7 4
===========================================================
solution 1 :
t : 1.00000000000000E+00 0.00000000000000E+00
m : 2
the solution for t :
y1 : 1.00000000000000E+00 6.36727435230003E-73
y2 : -3.81966011250105E-01 2.47616224811668E-73
y3 : -2.61803398874990E+00 -5.65979942426670E-73
y4 : 1.00000000000000E+00 -1.06121239205001E-73
== err : 4.785E-15 = rco : 7.860E-02 = res : 2.145E-72 ==
solution 2 :
t : 1.00000000000000E+00 0.00000000000000E+00
m : 2
the solution for t :
y1 : 3.09016994374947E-01 -9.51056516295154E-01
y2 : -8.09016994374947E-01 -5.87785252292473E-01
y3 : -8.09016994374948E-01 5.87785252292473E-01
y4 : 3.09016994374947E-01 9.51056516295154E-01
== err : 7.337E-16 = rco : 1.617E-01 = res : 2.483E-16 ==
solution 3 :
t : 1.00000000000000E+00 0.00000000000000E+00
m : 2
the solution for t :
y1 : 1.00000000000000E+00 3.70920615068742E-68
y2 : 1.00000000000000E+00 4.82196799589365E-67
y3 : -2.61803398874989E+00 1.48368246027497E-67
y4 : -3.81966011250105E-01 -1.03857772219248E-66
== err : 4.655E-15 = rco : 4.742E-02 = res : 4.441E-16 ==
solution 4 :
t : 1.00000000000000E+00 0.00000000000000E+00
m : 2
the solution for t :
y1 : -3.81966011250105E-01 2.84867032372794E-65
y2 : -3.81966011250105E-01 5.19288861096239E-66
y3 : -3.81966011250105E-01 0.00000000000000E+00
y4 : 1.45898033750316E-01 -3.32344871101593E-65
== err : 4.869E-16 = rco : 3.777E-02 = res : 5.551E-17 ==
solution 5 :
t : 1.00000000000000E+00 0.00000000000000E+00
m : 2
the solution for t :
y1 : 1.00000000000000E+00 7.07474928033337E-73
y2 : 1.00000000000000E+00 -4.52783953941336E-72
y3 : -3.81966011250105E-01 -3.53737464016669E-73
y4 : -2.61803398874989E+00 3.96185959698669E-72
== err : 4.655E-15 = rco : 4.136E-02 = res : 4.441E-16 ==
solution 6 :
t : 1.00000000000000E+00 0.00000000000000E+00
m : 2
the solution for t :
y1 : 6.85410196624969E+00 -2.65993991496909E-75
y2 : -2.61803398874989E+00 3.45446742203778E-76
y3 : -2.61803398874990E+00 7.94527507068689E-76
y4 : -2.61803398874990E+00 1.41633164303549E-75
== err : 5.029E-15 = rco : 1.653E-02 = res : 1.066E-14 ==
solution 7 :
t : 1.00000000000000E+00 0.00000000000000E+00
m : 2
the solution for t :
y1 : -8.09016994374947E-01 5.87785252292473E-01
y2 : 3.09016994374947E-01 -9.51056516295154E-01
y3 : 3.09016994374947E-01 9.51056516295154E-01
y4 : -8.09016994374947E-01 -5.87785252292473E-01
== err : 7.252E-16 = rco : 1.925E-01 = res : 5.551E-16 ==