>>You can see my solution in the thread I mentioned to Tore - I also first need to convert to decimal and make a pick on the precision. I chose 11 digits as using higher precision changes the original number (as it was float 0.99 it will become 0.98000089, something like that).
>
>Find the number of decimal of a float is a waste of time,
>because a solution does not exist.
>Some floats have an infinite number of decimal places,
>so we must first convert them into decimals.
>At this point the problem becomes to find the number of decimal places of a decimal ...

I agree. So, how do you find a number of decimal places of a decimal?