p "-1.2 56 0.443 4.22E-12 000555".scan(
/(?:[+-])?[0-9]+(?:[,.][0-9]+)?(?:E[+-][1-9][0-9]*)?/ )
#=> ["-1.2", "56", "0.443", "4.22E-12", "000555"]

This looks okay for most purposes, in my opinion. :)
You can google for "real number regex" et cetera...

Daniel Baird schrieb:
>> > On 8/4/06, Robert Retzbach <rretzbach / googlemail.com> wrote:
>> > > What about "1a2+b".scan(/\d+) ?
>> > > It returns the numbers as array.
>>
>> Will this pick up negative numbers or floats?
>>
> 
> Nope, only plain digits.  if you want other stuff, you need to add it
> to the regex.
> /\d+/  ..is just digits
> /[+-]?\d+/  ..optional + or -
> /[+-]?\d+\.?\d*/  ..optional + or -, and optional .
> 
> untested.. (sorry, too lazy to test :)
>