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: syz : Macros in libraries : rrank


[ideal J vlist] saturations jjj
It returns (ideal : J^\infty) 
Saturation is computed in the ring of polynomials.
When J=[f_1, f_2, ...], it is equal to 
((ideal, z-(f_1 + y f_2 + y^2 f_3 +...)) : z^\infty) \cap k[x].
Example 1:   
           [[(x1 y1 + x2 y2 + x3 y3 + x4 y4) 
             (x2 y2 + x4 y4) (x3 y3 + x4 y4) (y1 y4 - y2 y3)]
            [(y1) (y2) (y3) (y4)] (x1,x2,x3,x4,y1,y2,y3,y4)] saturation
            /ff set [ff (x1,x2,x3,x4,y1,y2,y3,y4) 
                     [[(y1) 1 (y2) 1 (y3) 1 (y4) 1]]] pgb 
            0 get [(y1) (y2) (y3) (y4)] eliminatev ::
Example 2: [[(x2^2) (x2 x4) (x2) (x4^2)] [(x2) (x4)] (x2,x4)] saturation

Nobuki Takayama 平成22年2月8日