D.5.4.6 spectrum

Procedure from library gaussman.lib (see gaussman_lib).

Usage:

spectrum(t); poly t

Assume:

characteristic 0; local degree ordering;
isolated critical point 0 of t

Return:

list sp; singularity spectrum of t ideal sp[1]; number sp[1][i]; i-th spectral number intvec sp[2]; int sp[2][i]; multiplicity of i-th spectral number

Example:

LIB "gaussman.lib";
ring R=0,(x,y),ds;
poly t=x5+x2y2+y5;
spprint(spectrum(t));
→ (-1/2,1),(-3/10,2),(-1/10,2),(0,1),(1/10,2),(3/10,2),(1/2,1)

See also: spectrum_lib.