feature-proposal: automatic international numbernotation

[GoogleCodeExporter]

Pgf-pie is really nice. But I lack one feature: numbernotation according to my 
region/country. American/English notation has for instance a dot between 
decimals. For instance: the half of one is 0.5. In my country(Belgium) the dot 
is a comma: 0,5. 
I did a little modification in de pgf-pie.sty so that it works for the normal 
slice In line 60 I adjusted the line to:
{\scalefont{#3}\beforenumber\pgfmathprintnumber[use comma]{#3}\afternumber};

Then it switched to mathfont... To solve this problem I modified it with 

{\scalefont{#3}\beforenumber\pgfmathprintnumber[assume math mode=true, use 
comma]{#3}\afternumber};



My question: is it possible to change automatically to the correct 
region-specific numbernotation on basis of the babel-settings (or somewhere 
else)? 

Original issue reported on code.google.com by koen.w...@gmail.com on 8 May 2014 at 7:00

[yguilhem]

There might be a way using \num{} and \SI{}{} commands from siunitx package.