public static double sqrtQuick(final double value){
  if (USE_JDK_MATH) {
    return Math.sqrt(value);
  }
  final long bits=Double.doubleToRawLongBits(value);
  return Double.longBitsToDouble(bits + 4606859074900000000L >>> 1);
}

public static double sqrtQuick ( final double value ) { if ( USE_JDK_MATH ) { return Math . sqrt ( value ) ; } final long bits = Double . doubleToRawLongBits ( value ) ; return Double . longBitsToDouble ( bits + 4606859074900000000L > > > 1 ) ; }
quick sqrt , with with a max relative error of about 3 . 41e - 2 for values in [ double . min_normal , double . max_value ] , and worse accuracy outside this range .
