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7.7.7.0. ivMis2Base
Procedure from library fpadim.lib (see fpadim_lib).

Usage:
ivMis2Base(M); M a list of intvecs

Return:
ideal, a K-base of the given algebra

Purpose:
Computing the K-base out of given mistletoes

Assume:
- The mistletoes have to be ordered lexicographically -> OrdMisLex.
Otherwise there might some elements missing.
- basering is a Letterplace ring.
- mistletoes are stored as intvecs, as described in the overview

Example:
 
LIB "fpadim.lib";
ring r = 0,(x,y),dp;
def R = makeLetterplaceRing(5); // constructs a Letterplace ring
R;
==> // coefficients: QQ
==> // number of vars : 10
==> //        block   1 : ordering a
==> //                  : names    x(1) y(1) x(2) y(2) x(3) y(3) x(4) y(4) x(\
   5) y(5)
==> //                  : weights     1    1    1    1    1    1    1    1   \
    1    1
==> //        block   2 : ordering dp
==> //                  : names    x(1) y(1)
==> //        block   3 : ordering dp
==> //                  : names    x(2) y(2)
==> //        block   4 : ordering dp
==> //                  : names    x(3) y(3)
==> //        block   5 : ordering dp
==> //                  : names    x(4) y(4)
==> //        block   6 : ordering dp
==> //                  : names    x(5) y(5)
==> //        block   7 : ordering C
setring R; // sets basering to Letterplace ring
intvec i1 = 1,2; intvec i2 = 2,1,2;
// the mistletoes are xy and yxy, which are already ordered lexicographically
list L = i1,i2;
ivMis2Base(L); // returns the basis of the factor algebra
==> [1]:
==>    2
==> [2]:
==>    2,1
==> [3]:
==>    2,1,2
==> [4]:
==>    1
==> [5]:
==>    1,2
==> [6]:
==>    0