private double boxRadius(int i,int a,int b){
  final int level;
  if (a < 0) {
    if (b >= pf.length) {
      return Double.POSITIVE_INFINITY;
    }
    level=maxRegLevel(i,b);
  }
 else   if (b >= pf.length) {
    level=maxRegLevel(i,a);
  }
 else {
    level=Math.max(maxRegLevel(i,a),maxRegLevel(i,b));
  }
  return minDistLevel(pf[i].id,level);
}

private double boxRadius ( int i , int a , int b ) { final int level ; if ( a < 0 ) { if ( b >= pf . length ) { return Double . POSITIVE_INFINITY ; } level = maxRegLevel ( i , b ) ; } else if ( b >= pf . length ) { level = maxRegLevel ( i , a ) ; } else { level = Math . max ( maxRegLevel ( i , a ) , maxRegLevel ( i , b ) ) ; } return minDistLevel ( pf [ i ] . id , level ) ; }
boxradius function calculate the boxradius
