Singular

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 ```