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D.6.15.1 spectrumnd

Procedure from library spectrum.lib (see spectrum_lib).

Usage:
spectrumnd(f[,1]); poly f

Assume:
basering has characteristic 0 and local ordering,
f has isolated singularity at 0 and nondegenerate principal part

Return:
 
list S:
  ideal S[1]: spectral numbers in increasing order
  intvec S[2]:
    int S[2][i]: multiplicity of spectral number S[1][i]

Note:
if a second argument 1 is given,
no test for a degenerate principal part will be done
SEE_ALSO: gmssing_lib

Example:
 
LIB "spectrum.lib";
ring R=0,(x,y),ds;
poly f=x^31+x^6*y^7+x^2*y^12+x^13*y^2+y^29;
list s=spectrumnd(f);
size(s[1]);
==> 174
s[1][22];
==> -27/58
s[2][22];
==> 2