CASA Function: implOffset

Computes the offset curve in implicit representation to a given curve.

Calling Sequence:

• S := implOffset(C)
• S := implOffset(C,d)
• S := implOffset(C,d,variables)

Parameters:

C : {algset("impl"),algset("para")}

• Algebraic curve in implicit or parametric representation,

d : {name,rational }

• A variable or a rational number, specifying the distance of the offset curve to the original curve.

variables : list(name)

• A list of two names for the representation of the resulting curve.

Result:

S : algset("impl")

• The offset curve in implicit representation.

Description:

• The function computes the offset curve in implicit representation at distance d to a given plane algebraic curve (in implicit or parametric representation).
• If the parameter d is not provided it is assumed that the distance is a parameter.
• If the parameter variables is not provided and the curve is given in implicit form and the parameter d does not belong to the variable list of C then this variable list is taken as default.

Examples:

> a:=mkImplAlgSet([x^2-y],[x,y]);

> implOffset(a,2);

> a:=mkParaAlgSet([2*t/(t^2+1),(t^2-1)/(t^2+1)],[t]);

> [implOffset(a)];

> [implOffset(a,d)];

See Also: