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7.2.6.1 resolution declarations (plural)

Syntax:
resolution name = resolution_expression ;

Purpose:
defines a resolution.

Default:
none

Example:
 
ring r=0,(x,y,z),dp;
matrix D[3][3];
D[1,2]=z;
def R=nc_algebra(1,D); // it is a Heisenberg algebra
setring R;
ideal i=z2+z,x+y;
resolution re=nres(i,0);
re;
==>  1      2      1      
==> R <--  R <--  R
==> 
==> 0      1      2      
==> resolution not minimized yet
==> 
list l = re;
l;
==> [1]:
==>    _[1]=z2+z
==>    _[2]=x+y
==> [2]:
==>    _[1]=z2*gen(2)-x*gen(1)-y*gen(1)+z*gen(2)
==> [3]:
==>    _[1]=0
print(matrix(l[2]));
==> -x-y,
==> z2+z 
print(module(transpose(matrix(l[2]))*transpose(matrix(l[1]))));  // check that product is zero
==> 0