macRes -- returns a matrix associated to the Macaulay resultant

Synopsis

• Usage:

  macRes(aSingleRowMatrix, varList)

• Inputs:

  • aSingleRowMatrix, a matrix, a single row matrix with polynomials f1,...,fn
  • varList, a list, a list of n variables such that the polynomials f1,...,fn are homogeneous with respect to these variables
• Outputs:

  • Matrix, a matrix, a generically surjective matrix such that the gcd of its maximal minors if the Macaulay resultant of f1,...,fn with respect to the variables 'varList'

Description

i1 : R=QQ[a..i,x,y,z]

o1 = R

o1 : PolynomialRing

i2 : f1 = a*x+b*y+c*z

o2 = a*x + b*y + c*z

o2 : R

i3 : f2 = d*x+e*y+f*z

o3 = d*x + e*y + f*z

o3 : R

i4 : f3 = g*x+h*y+i*z

o4 = g*x + h*y + i*z

o4 : R

i5 : M = matrix{{f1,f2,f3}}

o5 = | ax+by+cz dx+ey+fz gx+hy+iz |

             1       3
o5 : Matrix R  <--- R

i6 : l = {x,y,z}

o6 = {x, y, z}

o6 : List

i7 : MR = macRes (M,l)

o7 = {1} | a d g |
     {1} | b e h |
     {1} | c f i |

             3       3
o7 : Matrix R  <--- R

See also

• degMap -- This function returns the matrix of coefficients of the morphism of free modules 'm' in the variables 'var'
• macaulayFormula -- returns two matrices such that the ratio of their determinants is the Macaulay resultant
• detComplex -- This function calculates the determinant of a graded ChainComplex with respect to a subset of the variables of the polynomial ring in a fixed degree.
• listDetComplex -- This function calculates the list with the determinants of some minors of the maps of a graded ChainComplex with respect to a subset of the variables of the polynomial ring in a fixed degree.
• minorsComplex -- This function calculates some minors of the maps of a graded ChainComplex with respect to a subset of the variables of the polynomial ring in a fixed degree. The choice of the minors is according to the construction of the determinant of a complex
• mapsComplex -- This function calculates the maps of a graded ChainComplex with respect to a subset of the variables of the polynomial ring in a fixed degree.