// Copyright 2010 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. package cmplx import "math" // Phase returns the phase (also called the argument) of x. // The returned value is in the range [-Pi, Pi]. func Phase(x complex128) float64 { return math.Atan2(imag(x), real(x)) }