13.16.13  Checking if two circles in the plane are orthogonal: is_orthogonal

See Section 14.13.5 for checking for orthogonality in three-dimensional geometry.

The is_orthogonal command determines whether or not two lines or circles are orthogonal.

• is_orthogonal takes two arguments:
  C₁,C₂, two objects, both lines or both circles.
• is_orthogonal(C₁,C₂) returns 1 if C₁ and C₂ are orthogonal and returns 0 otherwise.

Examples.

• Input:
  is_orthogonal(line(0,1+i),line(i,1))
  Output:

  1

• Input:
  is_orthogonal(line(2,i),line(0,1+i))
  Output:

  0

• Input:
  is_orthogonal(circle(0,1+i),circle(2,1+i))
  Output:

  1

• Input:
  is_orthogonal(circle(0,1),circle(2,1))
  Output:

  0