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

Usage:
ivDimCheck(L,n); L a list of intmats, n an integer

Return:
int, 0 if the dimension is finite, or 1 otherwise

Purpose:
Decides, whether the K-dimension is finite or not

Assume:
- basering is a Letterplace ring
- All rows of each intmat correspond to a Letterplace monomial
For the encoding of the variables see the overview.

Note:
- n is the number of variables

Example:
 
LIB "fpadim.lib";
ring r = 0,(x,y),dp;
def R = makeLetterplaceRing(5); // constructs a Letterplace ring
R;
==> //   characteristic : 0
==> //   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
//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 and which
ivDimCheck(G,2); // invokes the procedure, factor is of finite K-dimension
==> 0
ivDimCheck(I,2); // invokes the procedure, factor is not of finite K-dimension
==> 1