2 bugs in classify.lib

[seelisch]

type=bug version=3-0-4 platform=Unix request=Actually 2 bugs in classify.lib:

1: classify(normalform("W#[1,r]")) gives output W#[1,r+1].

Examples: LIB "classify.lib"; ring R=0,(y,x),ds; poly f; f=normalform("W#[1,2]"); classify(f); quit;

yielded the following output:

About the singularity :

Milnor number(f) = 17 Corank(f) = 2 Determinacy <= 11

Guessing type via Milnorcode: W#[k,2r]=W[1,2]

Computing normal form ...

Arnold step number 32

The singularity

x4+2x2y3+x2y4+y6+xy6

is R-equivalent to W#[1,3].

Milnor number = 17 modality = 2

y4+2y2x3+x6+yx6+x8 Auf Wiedersehen.

The same for W#[1,3]: LIB "classify.lib"; ring R=0,(y,x),ds; poly f; f=normalform("W#[1,2]"); classify(f); quit;

yields

About the singularity :

Milnor number(f) = 18 Corank(f) = 2 Determinacy <= 11

Guessing type via Milnorcode: W#[k,2r-1]=W[1,3]

Computing normal form ...

Arnold step number 32

The singularity

x4+2x2y3+y6+xy6+y8

is R-equivalent to W#[1,4].

Milnor number = 18 modality = 2

y4+2y2x3+x6+y2x5+yx7

Second bug:

LIB "classify.lib"; ring R=0,(y,x),ds; poly f;

f=x6+y6+x3*y2+y3*x2; classify(f); f=x6+y7+x3*y2+y3*x2; classify(f); quit;

yielded the following output:

About the singularity :

Milnor number(f) = 18 Corank(f) = 2 Determinacy <= 10

? _ is undefined ? error occurred in classify.lib::debug_log line 2431: `parameter

int level; parameter list #; `

? leaving classify.lib::debug_log skipping text from ; error at token ) ? leaving classify.lib::HKclass7 ? leaving classify.lib::HKclass ? leaving classify.lib::Klassifiziere ? leaving classify.lib::classify

About the singularity :

Milnor number(f) = 19 Corank(f) = 2 Determinacy <= 11

? _ is undefined ? error occurred in classify.lib::debug_log line 2431: `parameter

int level; parameter list #; `

? leaving classify.lib::debug_log skipping text from ; error at token ) ? leaving classify.lib::HKclass7 ? leaving classify.lib::HKclass ? leaving classify.lib::Klassifiziere ? leaving classify.lib::classify

[seelisch]

bug report

[anne@…]

bug 1: misscount by 1 corrected for singularity W#[k,s] bug 2: special case now dealt with correctly

diffs sent to hannes@…, because I did not manage to check out Singular properly (slow line + really slow firewall)

[dreyer]

Anne's patch. Attention: maybe reversely diff'ed.

[dreyer]

Reved patch (forward and -u)

[dreyer]

Patch applied in revision # 1.54 of Singular/LIB/classify.lib.

[dreyer]

Patch seems to do its job.