String to Float, without introducing errors

[Peter J. Holzer]

On 2022-12-19 15:14:14 +0000, MRAB wrote:
> On 2022-12-19 14:10, Peter J. Holzer wrote:
> > He also interpreted the notation "6.67430(15)E-11" wrong. The
> > digits in parentheses represent the uncertainty in the same number of
> > last digits. So "6.67430(15)E-11" means "something between 6.67430E-11 -
> > 0.00015E-11 and 6.67430E-11 + 0.00015E-11".
[...]
> To be fair, I don't think I've never seen that notation either!

I've probably seen it first on Wikipedia, quite a few years ago. Since
then I've also encountered in in physical and astronomical papers (I'm
neither a physicist nor an astronomomer but I occasionally read the
original papers if what I read in the "mainstream media"[1] or hear on
youtube seems suspect).

> I've only ever seen the form 6.67430E-11 ± 0.00015E-11, which is much
> clearer.

Yeah, it's definitely not the pinnacle of inuitiveness. I freely admit
that I looked it up before posting just to make sure that I wasn't
confused about its meaning.

Another problem (but it shares that with the ± notation) is that it's
not clear what that number actually represents. Is it one sigma or two?
Or something else? Is the distribution even symmetric?

        hp

[1] I'm not quite happy with that term.

-- 
   _  | Peter J. Holzer    | Story must make more sense than reality.
|_|_) |                    |
| |   | hjp at hjp.at         |    -- Charles Stross, "Creative writing
__/   | http://www.hjp.at/ |       challenge!"
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