Home Online Manual
Top
Back: locus
Forward: envelop
FastBack:
FastForward:
Up: grobcov_lib
Top: Singular Manual
Contents: Table of Contents
Index: Index
About: About this document

D.2.4.13 locusdg

Procedure from library grobcov.lib (see grobcov_lib).

Usage:
locusdg(list L)
Calling sequence:
locusdg(locus(S)).

Return:
The output is the list of the "Relevant" components of the locus in Dynamic Geometry [C1,..,C:m], where
C_i= [p_i,[p_i1,..p_is_i], "Relevant", level_i]
The "Relevant" components are "Normal" and
"Accumulation" components of the locus. (See help
for locus).

Example:
 
LIB "grobcov.lib";
if(defined(R)){kill R;};
ring R=(0,a,b),(x,y),dp;
short=0;
// Concoid
ideal S96=x^2+y^2-4,(b-2)*x-a*y+2*a,(a-x)^2+(b-y)^2-1;
def L96=locus(S96);
L96;
==> [1]:
==>    [1]:
==>       _[1]=(a^4+2*a^2*b^2-9*a^2+b^4-9*b^2+4*b+12)
==>    [2]:
==>       [1]:
==>          _[1]=1
==>    [3]:
==>       [1]:
==>          1
==>       [2]:
==>          Normal
==>       [3]:
==>          _[1]=x^2+y^2-4
==> [2]:
==>    [1]:
==>       _[1]=(a^2+b^2-4*b+3)
==>    [2]:
==>       [1]:
==>          _[1]=1
==>    [3]:
==>       [1]:
==>          0
==>       [2]:
==>          Special
==>       [3]:
==>          _[1]=y^2-3*y+2
==>          _[2]=x^2+3*y-6
locusdg(L96);
==> [1]:
==>    [1]:
==>       _[1]=(a^4+2*a^2*b^2-9*a^2+b^4-9*b^2+4*b+12)
==>    [2]:
==>       [1]:
==>          _[1]=1
==>    [3]:
==>       [1]:
==>          1
==>       [2]:
==>          Relevant
==>       [3]:
==>          _[1]=x^2+y^2-4