D.5.8.14 tjurina

Procedure from library sing.lib (see sing_lib).

Usage:

tjurina(id); id=ideal or poly

Assume:

id=ICIS (isolated complete intersection singularity)

Return:

int = Tjurina number of id

Note:

Tjurina number = -1 implies that id is not an ICIS

Example:

LIB "sing.lib";
ring r=32003,(x,y,z),(c,ds);
ideal j=x2+y2+z2,x2+2y2+3z2;
tjurina(j);
→ 5