Hi Pieter,

Thanks for pointing this PR out. That certainly fixes the immediate problem 
with the inconsistent print statements that I highlighted in my original 
message.

It doesn't address the more fundamental problem, though, which is that the 
default behavior is to represent the polynomial in this rescaled form, which 
unnecessarily privileges numerical accuracy over ease of use and consistency 
with standard usage. I realize that it has been this way for a while, but 
multiple GitHub issues indicate that it causes confusion, which suggests that 
the issue should be addressed more meaningfully. (As an aside, the whole module 
uses a nonstandard definition of weights that also causes confusion.) I would 
expect the confusion to be compounded if Polynomial.fit (with its cousins) 
adopts the option to return the covariance matrix (which I recommend), since 
this will also depend on the scaling.

I think it's great to provide the *option* to scale the domain, especially for 
things like Chebyshev polynomials, where the domain typically needs rescaling, 
anyway. But a user who wants to fit data with y = a[0] + a[1] * x + a[2] * x**2 
should, IMO, get back the best-fit coefficients for the equation as originally 
formulated by default, not in the form that is most convenient for the 
numerical analyst.

Cheers,
Steve
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