Tom Lane <tgl@sss.pgh.pa.us> wrote:
> it would be interesting to know what Oracle etc do with NaN and
> Infinity, assuming they even support such numbers.
>
> Currently what our code does for the format-with-EEEE case is to
> output "#" in all digit positions. It would be plausible for that
> to happen in the non-EEEE cases too, but whether that's actually
> what happens in other systems is something I don't know.
From a quick web search, it looks like '#' filling is the typical
approach for infinity and NaN.
-Kevin