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7.7.7.0. ivSickle
Procedure from library fpadim.lib (see fpadim_lib).

Usage:
ivSickle(L,n,[degbound]); L a list of intmats, n an int, degbound an
optional integer

Return:
list, containing intvecs, the mistletoes of A/<L>

Purpose:
Computing the mistletoes for a given Groebner basis L, given by intmats

Assume:
- basering is a Letterplace ring.
- all rows of each intmat correspond to a Letterplace monomial
as explained in the overview
- if you specify a different degree bound degbound,
degbound <= attrib(basering,uptodeg) should hold.

Note:
- If degbound is set, a degree bound will be added. By default there
is no degree bound.
- n is the number of variables.
- If the K-dimension is known to be infinite, a degree bound is needed

Example:
 
LIB "fpadim.lib";
ring r = 0,(x,y),dp;
def R = makeLetterplaceRing(5); // constructs a Letterplace ring
setring R; // sets basering to Letterplace ring
//some intmats, which contain monomials in intvec representation as rows
intmat I1 [2][2] = 1,1,2,2; intmat I2 [1][3]  = 1,2,1;
intmat J1 [1][2] =  1,1; intmat J2 [2][3] = 2,1,2,1,2,1;
print(I1);
==>      1     1
==>      2     2
print(I2);
==>      1     2     1
print(J1);
==>      1     1
print(J2);
==>      2     1     2
==>      1     2     1
list G = I1,I2; // ideal, which is already a Groebner basis
list I =  J1,J2; // ideal, which is already a Groebner basis
ivSickle(G,2); // invokes the procedure without any degree bound
==> [1]:
==>    1,2
==> [2]:
==>    2,1,2
ivSickle(I,2,5); // invokes the procedure with degree bound 5
==> [1]:
==>    1,2,2,1
==> [2]:
==>    1,2,2,2,1
==> [3]:
==>    1,2,2,2,2
==> [4]:
==>    2,1
==> [5]:
==>    2,2,1
==> [6]:
==>    2,2,2,1
==> [7]:
==>    2,2,2,2,1
==> [8]:
==>    2,2,2,2,2


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