4.2 Resolutions

 Iterating the syz command yields a free resolution of a module or ideal. SINGULAR does this if the res or mres command is used.

Another algorithm due to Schreyer is presented in [S]. It will be used by the sres command.

For a comparision of these algorithms see [GG].

SINGULAR example:

ring r=0,(x,y,z),dp;
ideal I=x,y,z;
list Ir=res(I,0);
// print the results:
Ir;
list Im=mres(I,0);
// print the results:
Im;
list Is=sres(std(I),0);
// print the results:
Is;