Looks to me like r_min is set to r_min = 2 self.pf.h.get_smallest_dx() self.pf['mpc'], or thereabouts, from line 355 in yt/analysis_modules/halo_profiler/multi_halo_profiler.py. So it's grabbing a profile and setting the inner bin to that. The point on which it's centered is also not included, because you're asking for a log-spaced profile, and the log of 0 is a NaN.
So I guess the next question is, given these constraints, is it behaving as you'd expect?
I think that these 6 cells that are 2 self.pf.h.get_smallest_dx() self.pf['mpc'] - 1e-10 away perhaps should be included in the profile, and they're not. For all intents and purposes and numerical errors, the 6 cells are within that minimum radius, but they're not being included. So, either we make the minium halo profile radius larger such that we don't run into this error with zeroed inner bins, or we make the inner bin slightly smaller to account for numerical error. What do we all think?
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