freeVariables -- free variables of a triangular set

• Usage:

  freeVariables T

• Inputs:
  • T, an instance of the type TriaSystem,
• Outputs:
  • a list, of free variables of T

i1 : R = QQ[a,b,c,d,e,f,g,h, MonomialOrder=>Lex];

i2 : F = {a*d - b*c, c*f - d*e, e*h - f*g};

i3 : H = {d, f, h};

i4 : T = triaSystem(R,F,H)

o4 = {a*d - b*c, c*f - d*e, e*h - f*g} / {d, f, h}

o4 : TriaSystem

i5 : freeVariables T

o5 = {b, d, f, g, h}

o5 : List