|  |  5.1.55 highcorner 
See
 dim;
 std;
 vdim.Syntax:highcorner (ideal_expression)
 highcorner (module_expression)Type:poly, resp. vector
Purpose:returns the smallest monomial not contained in
the ideal, resp. module, generated by the initial terms of the given
generators. If the generators are a standard basis,
this is also the smallest monomial not contained in the ideal, resp. module.
If the ideal, resp. module, is not zero-dimensional, 0 is returned.
 The command works also in global orderings, but is not very useful there.
Note:Let the ideal I be given by a standard basis. Then
highcorner(I)returns 0 if and only ifdim(I)>0ordim(I)=-1.
Otherwise it returns the smallest monomial m not in I which has the following
properties (with the variables of the basering): 
if
 then  does not divide m (hence, m=1 if the ordering is global)
given any set of generators
 of I, let  be obtained from  by deleting the terms divisible by  for all i with  .
Then  generate I.Example:|  | ring r=0,(x,y),ds;
ideal i=x3,x2y,y3;
highcorner(std(i));
==> xy2
highcorner(std(ideal(1)));
==> 0
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