Conics

Here are all the conic curves valued functions:

• conic(A, l, x)
  Conic curve of focus A, directrix l and eccentricity x.
• conic(A, B, x)
  Conic curve of foci A and B. Number x is the half of the distance between the vertices (i.e. major axis for ellipses, or real axis for hyperbolas).
• parabola(A, l)
  Parabola of focus A and directrix l.
• parabola(A, x, a)
  Parabola of center A, such that x equals the semifocal chord and a the measure of the angle between the principal axis and the horizontal direction.
• ellipse(A, x, y, a)
  Ellipse of center A, such that x equals the half of the major axis, y the half of the minor axis and a the polar angle of the principal axis.
• hyperbola(A, x, y, a)
  Hyperbola of center A, such that x equals the half of the real axis, y the half of the imaginary axis and a the polar angle of the principal axis.
• translation(cc, u)
• reflection(cc, l)
• rotation(cc, A [, a])
  Rotation of center A and angle a (default: 180°).
• homothecy(cc, A, x)
  Homothecy, i.e. expansion or dilation, of center A and ratio x.

There are also the three following multiple assignments:

• A B foci(cc)
• A B vertices(cc)
• A B intersection(l, cc)