public double degRadius() {
        checkGeoCircle();
        return (this.r < 0) ? -1.0 : (0.000001 * this.r);
    }
Obtain circle radius (in degrees).
Note that "no radius" or "infinite radius" is represented as -1.
May only be called when isGeoCircle() returns true.
container-search/src/main/java/com/yahoo/prelude/Location.java