// circle.cpp // Member function definitions for class Circle #include "circle.h" // Constructor for Circle calls constructor for Point // with a member initializer then initializes radius. Circle::Circle( double r, int a, int b ) : Point( a, b ) // call base-class constructor { setRadius( r ); } // Set radius of Circle void Circle::setRadius( double r ) { radius = ( r >= 0 ? r : 0 ); } // Get radius of Circle double Circle::getRadius() const { return radius; } // Calculate area of Circle double Circle::area() const { return 3.14159 * radius * radius; } // Output a Circle in the form: // Center = [x, y]; Radius = #.## ostream &operator<<( ostream &output, const Circle &c ) { output << "Center = " << static_cast< Point >( c ) << "; Radius = " << setiosflags( ios::fixed | ios::showpoint ) << setprecision( 2 ) << c.radius; return output; // enables cascaded calls }