Does this function have a name?
For a, b > 0, max(a/b, b/a)

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@christianp I don't recall ever encountering a standard name for it! If I were using it I might be tempted to call it "absolute ratio" by analogy with the pretty common phrase "absolute difference."

It seems like your function comes from a more primitive one-variable function, max(x,1/x). And you can make the relationship to absolute value explicit by writing that as exp(abs(log(x))) if you're into that kind of thing, I guess. None of this does much to answer your question, but your function is interesting and I wish to subscribe to your newsletter.

@jsiehler yeah, I suppose the one-variable version is just as useful. Someone on twitter said min is better than max because it's range is [0,1], and called it 'squareness'. I like 'absolute ratio' too.

@christianp Logarithm of this function, max (log a - log b, log b - log a), would be just the distance |log a - log b|. So I might call it something like "multiplicative distance" or "relative distance".

@christianp It's the condition number of the matrix \(\begin{bmatrix}a&\\&b\end{bmatrix}\), but I agree with "aspect ratio" which I was going to independently suggest

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