How to move a circle $e^{i \pi n}$ along the $\Re$ axis to form a sine wave?

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Is there a way to move the unit circle $e^{i \pi n}$ where $n \in \mathbb{R}$ along the real axis to form a sine wave?

I know I can just replace the $\Re$ part of the result with $n$ but is there a mathematical way of doing that?

Something like $ 2 n \pi + e^{ni/ \pi}$ (below) but an exact sine wave resembling $y=sin(\pi x)$? The wavelength of the graph below is 125.4...

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Using complex numbers, a sine wave can be represented as

$$at+ib\sin t$$ where $a$ and $b$ are scaling factors. In terms of the complex exponential,

$$at+\frac b2(e^{it}-e^{-it}).$$


If you absolutely want to "move a circle", which I understand as "consider the trajectory of a point of a rotating circle the center of which moves horizontally" (?), you need to solve

$$x(t)+be^{it}=at+ib\sin t$$ which tells you the motion of the center,

$$x(t)=at-b\cos t.$$

Finally,

$$at-b\cos t+be^{it}$$ which does not seem any better than the very first expression.


Note that the expression

$$at+be^{it}$$ describes a trochoid, a special case of which is a cycloid.