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Oct 22, 2023 at 14:07 comment added lotus2019 @josh What is the code for radialPlot?
Aug 17, 2022 at 15:53 history edited josh CC BY-SA 4.0
Added level curve plot
Aug 17, 2022 at 15:48 comment added josh @Michael E2: I added a level-curve plot to the radial branch as an edit to my code above. Maybe this is what the OP wanted.
Aug 17, 2022 at 15:47 history edited josh CC BY-SA 4.0
Added level curve plot
Aug 17, 2022 at 15:21 comment added josh @Michael E2: Ok, I re-read it: Looks like the OP wishes to have perhaps a ComplexContourPlot over the indicated branch as his request to replace Plot3D with ContourPlot in an earlier comment. I'll try to do that over the radial branch I created.
Aug 17, 2022 at 14:51 comment added Michael E2 Yes, I see. We have different understandings of the what the OP wants.
Aug 17, 2022 at 14:49 comment added josh @Michael E2: As I understand the problem, the OP wishes to extract an analytically-continuous and single-valued section or "branch" from this multi-valued funtion equal to the sector $e^{it}$ for $\theta<t<\pi-\theta$. This sector does not impinge the singular points so has no discontinuity between it and the remainder of the sheets as I show in the plot with label "Im(f) with radial branch". Perhaps thouogh this is not what the OP wishes.
Aug 17, 2022 at 14:40 comment added Michael E2 And so what you drew is incorrect? Or rather, not in agreement with my understanding of the question? — I was thinking that @DuFong would clarify. I'm just surprised that there is no discontinuity along the proposed branch cut.
Aug 17, 2022 at 14:21 comment added josh @Michael E2: There is no discontinuity between the radial branch $\theta<t<\pi-\theta$ as I've drawn it above and the remainder of the multivalued sheets. That radial section is simply an analytic domain of the function which does not involve any of its singular points which is equivalent to taking the disc $1+1/2 e^{it}$ out of $\sqrt{z}$ .
Aug 17, 2022 at 14:09 comment added Michael E2 @DuFong, josh: I'd expect to see each plot of the real and imaginary parts to be a surface over the complex plane with a discontinuity only along the arc of the unit circle parametrized by $z=e^{it}$, $\theta \le t \le \pi-\theta$, according how I've understood the question. But I haven't yet thought of an approach that is simple enough I want to try it. — Is that the right idea, though?
Aug 17, 2022 at 10:57 history edited josh CC BY-SA 4.0
corrected typo in description of branch cuts
Aug 17, 2022 at 10:56 comment added josh @DuFong: Sorry, I don't understand your question. Maybe you can explain further. Also there is likely an analytic method of directly representing a desired branch by an analytic expression using perhaps $z_1=r_1e^{i t_1}$ and $z_2=r_2 e^{i t_2}$ in the expression for $f$.
Aug 16, 2022 at 20:57 comment added DuFong is it possible to project to the complex plane (say, replace Plot3D by ContourPlot?)
Aug 16, 2022 at 20:53 history edited josh CC BY-SA 4.0
Added radial branch described by OP
Aug 16, 2022 at 17:45 history edited josh CC BY-SA 4.0
Made more clear and easier to follow
Aug 16, 2022 at 16:03 history answered josh CC BY-SA 4.0