Class Circle

constructor

• new Circle(): Circle

  Returns Circle

• new Circle(equation: string | Equation): Circle

  Parameters

  • equation: string | Equation

  Returns Circle

• new Circle(circle: Circle): Circle

  Parameters

  • circle: Circle

  Returns Circle

• new Circle(center: Point, radius: number | Fraction, square?: boolean): Circle

  Parameters

  • center: Point
  • radius: number | Fraction
  • Optionalsquare: boolean

  Returns Circle

• new Circle(center: Point, pointThrough: Point): Circle

  Parameters

  • center: Point
  • pointThrough: Point

  Returns Circle

• new Circle(A: Point, B: Point, C: Point): Circle

  Parameters

  • A: Point
  • B: Point
  • C: Point

  Returns Circle

StaticRELATIVE_POSITION

asCenterRadius

• get asCenterRadius(): this

  Output option: the form (x-a)^2+(y-b)^2=r^2 (default). Chainable, persistent.

  Returns this

asDeveloped

• get asDeveloped(): this

  Output option: the developed equation x^2+y^2-2x+4y-4=0. Chainable, persistent.

  Returns this

center

• get center(): Point

  The center, as a point.

  Returns Point

display

• get display(): string

  ASCIIMath rendering of the current state (terminal output, not chainable).

  Returns string

equation

• get equation(): Equation

  The equation (x-a)^2+(y-b)^2-r^2=0, as an Equation (a copy).

  Returns Equation

radius

• get radius(): Root

  The radius, as an exact reduced Root (3, 2sqrt(2)).

  Returns Root

squareRadius

• get squareRadius(): Fraction

  The square of the radius, as an exact fraction. It is -1 for a circle that has not been defined.

  Returns Fraction

tex

• get tex(): string

  LaTeX rendering of the current state (terminal output, not chainable).

  Returns string

clone

• clone(): this

  Full duplicate of this instance, including display state (selected form and options set via as*** / with***). Distinct from copy.

  Returns this

copy

• copy(circle: Circle): this

  Copy the mathematical state of another instance into this (display state is NOT transferred — the receiver keeps its own formatting). Entry point used when constructing/parsing from a same-type input. Distinct from clone. Classes without a real implementation throw NotImplementedError.

  Parameters

  • circle: Circle

  Returns this

getPointsOnCircle

• getPointsOnCircle(): Point[]

  The points of the circle with integer coordinates relative to the center. It is empty when the square of the radius is not an integer.

  Returns Point[]

intersection

• intersection(L: Line): Point[]

  Find the intersection points between the circle and a line. It can be 0, 1 or 2 points. The points are sorted depending on the direction vector of the line.

  Parameters

  • L: Line

  Returns Point[]

isEqual

• isEqual(circ: Circle): boolean

  True when both circles have the same center and the same radius.

  Parameters

  • circ: Circle

  Returns boolean

isPointOnCircle

• isPointOnCircle(P: Point): boolean

  True when the point satisfies the equation of the circle.

  Parameters

  • P: Point

  Returns boolean

parse

• parse(...values: unknown[]): this

  Replace the circle with an equation, another circle, a center and a radius, a center and a point, or three points. Arguments that do not match any form leave the circle unchanged.

  Parameters

  • ...values: unknown[]

  Returns this

relativePosition

• relativePosition(L: Line): 0 | 1 | 2

  Returns the number of intersections between circle and line.

  Parameters

  • L: Line

  Returns 0 | 1 | 2

  0 = external, 1 = tangent, 2 = secant

  Throws

  if the circle is uninitialized

• relativePosition(C: Circle): CircleRelativePosition

  Returns the relative position between two circles.

  Parameters

  • C: Circle

  Returns CircleRelativePosition

  Throws

  if the circle is uninitialized

setRadius

• setRadius(radius: number | Fraction, square?: boolean): this

  Change the radius.

  Parameters

  • radius: number | Fraction
  • Optionalsquare: boolean

    when true, radius is the square of the radius.

  Returns this

tangents

• tangents(P: Fraction | Point): Line[]

  Returns the tangent line(s) to the circle.

  • P: Point on the circle → 1 tangent (perpendicular to the radius at P).
  • P: Point outside the circle → 2 tangents through P.
  • P: Point inside the circle → [] (no real tangent).
  • P: Fraction → 2 tangents with slope P.

  Parameters

  • P: Fraction | Point

  Returns Line[]

withDigits

• withDigits(digits: number | null): this

  Parameters

  • digits: number | null

  Returns this

  See

  IDisplayDigits.withDigits

StaticfromCenterPoint

• fromCenterPoint(center: Point, pointThrough: Point): Circle

  The circle with the given center, through a point.

  Parameters

  • center: Point
  • pointThrough: Point

  Returns Circle

StaticfromCenterRadius

• fromCenterRadius(
      center: Point,
      radius: number | Fraction,
      square?: boolean,
  ): Circle

  The circle with the given center and radius.

  Parameters

  • center: Point
  • radius: number | Fraction
  • Optionalsquare: boolean

    when true, radius is already the square of the radius.

  Returns Circle

StaticfromEquation

• fromEquation(value: InputAlgebra<Equation>): Circle

  Does not mutate the input.

  Parameters

  • value: InputAlgebra<Equation>

  Returns Circle

  Throws

  if the input is not a valid circle equation

StaticfromPoints

• fromPoints(A: Point, B: Point, C: Point): Circle

  The circle through three points.

  Parameters

  • A: Point
  • B: Point
  • C: Point

  Returns Circle

  Throws

  if the points are collinear or two of them are the same.

StaticfromString

• fromString(str: string): Circle

  The circle of an equation written in a string.

  Parameters

  • str: string

  Returns Circle

  Throws

  if the equation is not the one of a circle.