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SparseResultants :: denseDiscriminant

denseDiscriminant -- dense discriminant (classical discriminant)

Synopsis

Description

i1 : (d,n) := (2,3);
i2 : time Disc = denseDiscriminant(d,n)
     -- used 0.182159 seconds

o2 = Disc

o2 : SparseDiscriminant (sparse discriminant associated to | 0 0 0 0 0 0 1 1 1 2 |)
                                                           | 0 0 0 1 1 2 0 0 1 0 |
                                                           | 0 1 2 0 1 0 0 1 0 0 |
i3 : f = first genericLaurentPolynomials prepend(d,n:0)

        2               2                        2
o3 = a x  + a x x  + a x  + a x x  + a x x  + a x  + a x  + a x  + a x  + a
      9 1    8 1 2    5 2    7 1 3    4 2 3    2 3    6 1    3 2    1 3    0

o3 : ZZ[a ..a , b , c , d ][x ..x ]
         0   9   0   0   0   1   3
i4 : assert(Disc(f) == denseDiscriminant(f))

See also

Ways to use denseDiscriminant :

For the programmer

The object denseDiscriminant is a method function with options.