Method eccentricity

libraries/ellipse/ellipse.cpp:79–85

float ellipse::eccentricity()
{
  if (_a == _b) return 0;  //  quick circle check.
  float x = _a * _a - _b * _b;
  if (x < 0) x = -1 * x;
  return sqrt(x)/ _a;
}


bool ellipse::isCircle(float epsilon)