On Fri, Feb 13, 2015 at 4:56 PM, nicolas cellier <nicolas.cellier.aka.nice@gmail.com> wrote:

...

If it's for monetary things like computing interests, then the advice is to
not use Float but ScaledDecimal.

100 * (1.05s2 raisedTo: 10) roundTo: 0.01s2
-> 162.89s2

Nicolas

So, for money, I would suggest not using ScaledDecimal, but rather FixedDecimal.

ScaledDecimal can do funny things that you would not expect in real money land:

m := 1/3 asScaledDecimal: 2.

m "==> 0.33s2"

m + m + m "==> 1.00s2"

You shouldn't be allowed to add 33 cents together and get a whole dollar (usd, at least)!

FixedDecimal actually rounds to the specified length (ScaledDecimal keeps the entire precision 'behind the curtains').

m := 1/3 asFixedDecimal: 2.

m "==> 0.33"

m + m + m "==> 0.99"

http://www.squeaksource.com/FixedDecimal.html

-cbc