Singular

LIB "gmssing.lib";
ring R=0,(x,y),ds;
list sp=list(ideal(-1/2,-3/10,-1/10,0,1/10,3/10,1/2),intvec(1,2,2,1,2,2,1));
spprint(sp);
==> (-1/2,1),(-3/10,2),(-1/10,2),(0,1),(1/10,2),(3/10,2),(1/2,1)
spprint(spmul(sp,2));
==> (-1/2,2),(-3/10,4),(-1/10,4),(0,2),(1/10,4),(3/10,4),(1/2,2)
list sp1=list(ideal(-1/6,1/6),intvec(1,1));
spprint(sp1);
==> (-1/6,1),(1/6,1)
list sp2=list(ideal(-1/3,0,1/3),intvec(1,2,1));
spprint(sp2);
==> (-1/3,1),(0,2),(1/3,1)
spprint(spmul(list(sp1,sp2),intvec(1,2)));
==> (-1/3,2),(-1/6,1),(0,4),(1/6,1),(1/3,2)