func math.xatan

4 uses

	math (current package)
		atan.go#L55: func xatan(x float64) float64 {
		atan.go#L82: 		return xatan(x)
		atan.go#L85: 		return Pi/2 - xatan(1/x) + Morebits
		atan.go#L87: 	return Pi/4 + xatan((x-1)/(x+1)) + 0.5*Morebits