case math.IsInf(re, 0):
		switch {
		case re > 0 && im == 0:
			return x
		case math.IsInf(im, 0) || math.IsNaN(im):
			if re < 0 {
				return complex(0, math.Copysign(0, im))
			} else {
				return complex(math.Inf(1.0), math.NaN())
			}
		}
	case math.IsNaN(re):
		if im == 0 {
			return complex(math.NaN(), im)
		}
	}
	r := math.Exp(real(x))
	s, c := math.Sincos(imag(x))

// This is an assembly implementation of the method used for function Exp in file exp.go.
//
// func Exp(x float64) float64
TEXT ·archExp(SB),$0-16
	FMOVD	x+0(FP), F0	// F0 = x
	FCMPD	F0, F0
	BNE	isNaN		// x = NaN, return NaN
	FMOVD	$Overflow, F1
	FCMPD	F1, F0
	BGT	overflow	// x > Overflow, return PosInf
	FMOVD	$Underflow, F1
	FCMPD	F1, F0
	BLT	underflow	// x < Underflow, return 0
	MOVD	$NearZero, R0

func Atan2(y, x float64) float64 {
	if haveArchAtan2 {
		return archAtan2(y, x)
	}
	return atan2(y, x)
}

func atan2(y, x float64) float64 {
	// special cases
	switch {
	case IsNaN(y) || IsNaN(x):
		return NaN()
	case y == 0:
		if x >= 0 && !Signbit(x) {
			return Copysign(0, y)
		}
		return Copysign(Pi, y)
	case x == 0:
		return Copysign(Pi/2, y)
	case IsInf(x, 0):
		if IsInf(x, 1) {

func Equal[Elem comparable](s1, s2 []Elem) bool {
	if len(s1) != len(s2) {
		return false
	}
	for i, v1 := range s1 {
		v2 := s2[i]
		if v1 != v2 {
			isNaN := func(f Elem) bool { return f != f }
			if !isNaN(v1) || !isNaN(v2) {
				return false
			}
		}
	}
	return true
}

// EqualFn reports whether two slices are equal using a comparison
// function on each element.

	if int32(hcmp) != scmp || hisnan != sisnan {
		err(t, "cmp(%g, %g) = sw %v, %v, hw %v, %v\n", f, g, scmp, sisnan, hcmp, hisnan)
	}
}

func same(f, g float64) bool {
	if math.IsNaN(f) && math.IsNaN(g) {
		return true
	}
	if math.Copysign(1, f) != math.Copysign(1, g) {
		return false
	}
	return f == g

//	Floor(±0) = ±0
//	Floor(±Inf) = ±Inf
//	Floor(NaN) = NaN
func Floor(x float64) float64 {
	if haveArchFloor {
		return archFloor(x)
	}
	return floor(x)
}

func floor(x float64) float64 {
	if x == 0 || IsNaN(x) || IsInf(x, 0) {
		return x
	}
	if x < 0 {
		d, fract := Modf(-x)
		if fract != 0.0 {
			d = d + 1
		}
		return -d
	}
	d, _ := Modf(x)
	return d
}

func _SlicesEqual[Elem comparable](s1, s2 []Elem) bool {
	if len(s1) != len(s2) {
		return false
	}
	for i, v1 := range s1 {
		v2 := s2[i]
		if v1 != v2 {
			isNaN := func(f Elem) bool { return f != f }
			if !isNaN(v1) || !isNaN(v2) {
				return false
			}
		}
	}
	return true
}

// _Keys returns the keys of the map m.
// The keys will be an indeterminate order.

func _SliceEqual[Elem comparable](s1, s2 []Elem) bool {
	if len(s1) != len(s2) {
		return false
	}
	for i, v1 := range s1 {
		v2 := s2[i]
		if v1 != v2 {
			isNaN := func(f Elem) bool { return f != f }
			if !isNaN(v1) || !isNaN(v2) {
				return false
			}
		}
	}
	return true
}

// A Graph is a collection of nodes. A node may have an arbitrary number

	switch re, im := real(x), imag(x); {
	case math.IsInf(im, 0):
		switch {
		case math.IsInf(re, 0) || math.IsNaN(re):
			return complex(math.Copysign(0, re), math.Copysign(1, im))
		}
		return complex(math.Copysign(0, math.Sin(2*re)), math.Copysign(1, im))
	case re == 0 && math.IsNaN(im):
		return x
	}
	d := math.Cos(2*real(x)) + math.Cosh(2*imag(x))
	if math.Abs(d) < 0.25 {
		d = tanSeries(x)
	}

func SliceEqual[Elem comparable](s1, s2 []Elem) bool {
	if len(s1) != len(s2) {
		return false
	}
	for i, v1 := range s1 {
		v2 := s2[i]
		if v1 != v2 {
			isNaN := func(f Elem) bool { return f != f }
			if !isNaN(v1) || !isNaN(v2) {
				return false
			}
		}
	}
	return true
}

// Ranger returns a Sender and a Receiver. The Receiver provides a