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D.4.7.14 zerodec
Procedure from library primdec.lib (see primdec_lib).
- Usage:
zerodec(I); I ideal
- Assume:
I is zero-dimensional, the characteristic of the ground field is 0
- Return:
list of primary ideals, the zero-dimensional decomposition of I
- Note:
The algorithm (of Monico), works well only for a small total number
of solutions (vdim(std(I)) should be < 100) and without
parameters. In practice, it works also in large characteristic p>0
but may fail for small p.
If printlevel > 0 (default = 0) additional information is displayed.
Example:
| LIB "primdec.lib";
ring r = 0,(x,y),dp;
ideal i = x2-2,y2-2;
list pr = zerodec(i);
pr;
→ [1]:
→ _[1]=y2-2
→ _[2]=xy-2
→ _[3]=x2-2
→ [2]:
→ _[1]=y2-2
→ _[2]=xy+2
→ _[3]=x2-2
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