|  |  D.6.11.5 displayHNE Procedure from libraryhnoether.lib(see  hnoether_lib).
 
Example:Usage:
displayHNE(L[,n]); L list, n int
Assume:
L is the output of develop(f), or ofexdevelop(f,n),
or ofhnexpansion(f[,"ess"]), or (one entry in) the listhnein the ring created byhnexpansion(f[,"ess"]).
Return:
- if only one argument is given and if the input are the HN data
of an irreducible plane curve singularity, no return value, but
display an ideal HNE of the following form:
where|  |        y = []*x^1+[]*x^2   +...+x^<>*z(1)
       x =        []*z(1)^2+...+z(1)^<>*z(2)
       z(1) =     []*z(2)^2+...+z(2)^<>*z(3)
       .......             ..........................
       z(r-1) =   []*z(r)^2+[]*z(r)^3+......
 | 
 x,yare the first 2 variables of the basering.
The values of[]are the coefficients of the Hamburger-Noether
matrix, the values of<>are represented byxin the
HN matrix.- if a second argument is given and if the input are the HN data
of an irreducible plane curve singularity, return a ring containing
an ideal
 HNEas described above.- if L corresponds to the output of
 hnexpansion(f)or to the list of HN data computed byhnexpansion(f[,"ess"]),displayHNE(L[,n])shows the HNE's of all branches of f in the
format described above. The optional parameter is then ignored.
Note:
The 1st line of the above ideal (i.e., HNE[1]) means thaty=[]*z(0)^1+..., the 2nd line (HNE[2]) means thatx=[]*z(1)^2+..., so you can see which indeterminate
corresponds to which line (it's also possible thatxcorresponds
to the 1st line andyto the 2nd).
 See also:
 develop;
 hnexpansion.|  | LIB "hnoether.lib";
ring r=0,(x,y),dp;
poly f=x3+2xy2+y2;
list hn=develop(f);
displayHNE(hn);
==>   y = z(1)*x
==>   x = -z(1)^2 + ..... (terms of degree >=3)
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