Singular Manual: Emaxcont

| #### D.5.12.12 Emaxcont Procedure from library `resbinomial.lib` (see resbinomial_lib). Usage: Emaxcont(Coef,Exp,k,n,flag); Coef,Exp,flag lists, k,n, integers Exp is a list of lists of exponents, k=size(Exp) Compute: Identify ALL the variables of E-maximal contact Return: a list with the indexes of the variables of E-maximal contact Example:
    LIB "resbinomial.lib";
    ring r = 0,(x(1),y(2),x(3),y(4),x(5..7),y(8)),dp;
    list flag=identifyvar();
    ideal J=x(1)^3*x(3)-y(2)*y(4)^2,x(5)*y(2)-x(7)*y(4)^2,x(6)^2*(1-y(4)*y(8)^5),x(7)^4*y(8)^2;
    list L=data(J,4,8);
    list hyp=Emaxcont(L[1],L[2],4,8,flag);
    hyp[1]; // max E-order=0
    ==> 0
    hyp[2]; // There are no hypersurfaces of E-maximal contact
    ==> empty list
    ring r = 0,(x(1),y(2),x(3),y(4),x(5..7),y(8)),dp;
    ==> // ** redefining r (ring r = 0,(x(1),y(2),x(3),y(4),x(5..7),y(8)),dp;) ./\
       examples/Emaxcont.sing:9
    list flag=identifyvar();
    ==> // ** redefining flag (list flag=identifyvar();) ./examples/Emaxcont.sing\
       :10
    ideal J=x(1)^3*x(3)-y(2)*y(4)^2*x(3),x(5)*y(2)-x(7)*y(4)^2,x(6)^2*(1-y(4)*y(8)^5),x(7)^4*y(8)^2;
    list L=data(J,4,8);
    list hyp=Emaxcont(L[1],L[2],4,8,flag);
    hyp[1]; // the E-order is 1
    ==> 1
    hyp[2]; // {x(3)=0},{x(5)=0},{x(7)=0} are hypersurfaces of E-maximal contact
    ==> [1]:
    ==>    3
    ==> [2]:
    ==>    7
    ==> [3]:
    ==>    5

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