D.6.15.7 displayInvariants

Usage:

displayInvariants(INPUT); INPUT list or poly

Assume:

INPUT is a bivariate polynomial, or the output of develop(f), resp. of extdevelop(develop(f),n), or (one entry of) the list of HN data computed by hnexpansion(f[,"ess"]).

Return:

none

Display:

invariants of the corresponding branch, resp. of all branches, in a better readable form.

Note:

If the Hamburger-Noether expansion of the curve f is needed for other purposes as well it is better to calculate this first with the aid of hnexpansion and use it as input instead of the polynomial itself.

LIB "hnoether.lib";
ring exring=0,(x,y),dp;
list Hne=develop(y4+2x3y2+x6+x5y);
displayInvariants(Hne);
==>  characteristic exponents  : 4,6,7
==>  generators of semigroup   : 4,6,13
==>  Puiseux pairs             : (3,2)(7,2)
==>  degree of the conductor   : 16
==>  delta invariant           : 8
==>  sequence of multiplicities: 4,2,2,1,1