G              = 3.57142857142857150787e-01  // 5/14      = 0x3FD6DB6DB6DB6DB7
		SmallestNormal = 2.22507385850720138309e-308 // 2**-1022  = 0x0010000000000000
	)
	// special cases
	switch {
	case x == 0 || IsNaN(x) || IsInf(x, 0):
		return x
	}

	sign := false
	if x < 0 {
		x = -x
		sign = true
	}

	// rough cbrt to 5 bits
	t := Float64frombits(Float64bits(x)/3 + B1<<32)
	if x < SmallestNormal {

		}
		got, err := ParseComplex(test.in, 128)
		if !reflect.DeepEqual(err, test.err) {
			t.Fatalf("ParseComplex(%q, 128) = %v, %v; want %v, %v", test.in, got, err, test.out, test.err)
		}
		if !(cmplx.IsNaN(test.out) && cmplx.IsNaN(got)) && got != test.out {
			t.Fatalf("ParseComplex(%q, 128) = %v, %v; want %v, %v", test.in, got, err, test.out, test.err)
		}

		if complex128(complex64(test.out)) == test.out {

	}

	return s[0]
}

func (s sorted) max() float64 {
	if len(s) == 0 {
		return infinity
	}

	return s[len(s)-1]
}

func (s sorted) quantile(phi float64) float64 {
	if len(s) == 0 || math.IsNaN(phi) {
		return nan
	}
	if phi <= 0 {
		return s.min()
	}
	if phi >= 1 {
		return s.max()
	}
	idx := uint(phi*float64(len(s)-1) + 0.5)
	if idx >= uint(len(s)) {
		idx = uint(len(s) - 1)
	}

		L6    = 1.531383769920937332e-01   /* 3FC39A09 D078C69F */
		L7    = 1.479819860511658591e-01   /* 3FC2F112 DF3E5244 */
	)

	// special cases
	switch {
	case math.IsNaN(x) || math.IsInf(x, 1):
		return x
	case x < 0:
		return math.NaN()
	case x == 0:
		return math.Inf(-1)
	}

	// reduce
	f1, ki := math.Frexp(x)
	if f1 < math.Sqrt2/2 {
		f1 *= 2
		ki--
	}

		PI4B = 3.77489470793079817668e-8  // 0x3e64442d00000000,
		PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
	)
	// special cases
	switch {
	case IsNaN(x) || IsInf(x, 0):
		return NaN()
	}

	// make argument positive
	sign := false
	x = Abs(x)

	var j uint64
	var y, z float64
	if x >= reduceThreshold {
		j, z = trigReduce(x)
	} else {

  }
}

dispatcher.onPost(/^\/ratings\/[0-9]*/, function (req, res) {
  var productIdStr = req.url.split('/').pop()
  var productId = parseInt(productIdStr)
  var ratings = {}

  if (Number.isNaN(productId)) {
    res.writeHead(400, {'Content-type': 'application/json'})
    res.end(JSON.stringify({error: 'please provide numeric product ID'}))
    return
  }

  try {
    ratings = JSON.parse(req.body)

//
//	Pow(0, ±0) returns 1+0i
//	Pow(0, c) for real(c)<0 returns Inf+0i if imag(c) is zero, otherwise Inf+Inf i.
func Pow(x, y complex128) complex128 {
	if x == 0 { // Guaranteed also true for x == -0.
		if IsNaN(y) {
			return NaN()
		}
		r, i := real(y), imag(y)
		switch {
		case r == 0:
			return 1
		case r < 0:
			if i == 0 {
				return complex(math.Inf(1), 0)
			}
			return Inf()
		case r > 0:

//	Jn(n, NaN) = NaN
func Jn(n int, x float64) float64 {
	const (
		TwoM29 = 1.0 / (1 << 29) // 2**-29 0x3e10000000000000
		Two302 = 1 << 302        // 2**302 0x52D0000000000000
	)
	// special cases
	switch {
	case IsNaN(x):
		return x
	case IsInf(x, 0):
		return 0
	}
	// J(-n, x) = (-1)**n * J(n, x), J(n, -x) = (-1)**n * J(n, x)
	// Thus, J(-n, x) = J(n, -x)

	if n == 0 {
		return J0(x)
	}
	if x == 0 {
		return 0

		PI4B = 3.77489470793079817668e-8  // 0x3e64442d00000000,
		PI4C = 2.69515142907905952645e-15 // 0x3ce8469898cc5170,
	)
	// special cases
	switch {
	case x == 0 || IsNaN(x):
		return x // return ±0 || NaN()
	case IsInf(x, 0):
		return NaN()
	}

	// make argument positive but save the sign
	sign := false
	if x < 0 {
		x = -x
		sign = true
	}
	var j uint64

		L6    = 1.531383769920937332e-01   /* 3FC39A09 D078C69F */
		L7    = 1.479819860511658591e-01   /* 3FC2F112 DF3E5244 */
	)

	// special cases
	switch {
	case IsNaN(x) || IsInf(x, 1):
		return x
	case x < 0:
		return NaN()
	case x == 0:
		return Inf(-1)
	}

	// reduce
	f1, ki := Frexp(x)
	if f1 < Sqrt2/2 {
		f1 *= 2
		ki--
	}
	f := f1 - 1