| On the real axis The function  along the real axis.  is an oscillating periodic function with period  that has first‐order poles at  . The absolute value and the argument of  along the real axis. The left graphic shows  and the right graphic shows  . The argument is piecewise constant. On the real axis at infinity The function  along the real axis. At  , the function has an essential singularity and oscillates infinitely often. The absolute value and the argument of  along the real axis. The left graphic shows  and the right graphic shows  . The argument is piecewise constant. On the imaginary axes The real part and the imaginary part of  along the imaginary axis. The left graphic shows  and the right graphic shows  . Along the imaginary axis,  is purely imaginary and vanishes identically. The absolute value and the argument of  along the imaginary axis. The left graphic shows  and the right graphic shows  . Because  is vanishes identically on the imaginary axis, the argument is 0 there. On the imaginary axis at infinity The function  along the imaginary axis. The left graphic shows  and the right graphic shows  . The absolute value and the argument of  along the imaginary axis. The left graphic shows  and the right graphic shows  . On the unit circle The real part and the imaginary part of  on the unit circle. The left graphic shows  and the right graphic shows  . The absolute value and the argument of on the unit circle. The left graphic shows  and the right graphic shows  . |