regex help

[MRAB]

On 2015-03-13 16:05, Larry Martell wrote:
> I need to remove all trailing zeros to the right of the decimal point,
> but leave one zero if it's whole number. For example, if I have this:
>
> 14S,5.0000000000000000,4.56862745000000,3.7272727272727271,3.3947368421052630,5.7307692307692308,5.7547169811320753,4.9423076923076925,5.7884615384615383,5.137254901960000
>
> I want to end up with:
>
> 14S,5.0,4.56862745,3.7272727272727271,3.394736842105263,5.7307692307692308,5.7547169811320753,4.9423076923076925,5.7884615384615383,5.13725490196
>
> I have a regex to remove the zeros:
>
> '0+[,$]', ''
>
> But I can't figure out how to get the 5.0000000000000000 to be 5.0.
> I've been messing with the negative lookbehind, but I haven't found
> one that works for this.
>
Search: (\.\d+?)0+\b
Replace: \1

which is:

re.sub(r'(\.\d+?)0+\b', r'\1', string)