Re: Financial Calculations in Ada

[Georg Bauhaus <rm.dash-bauhaus@futureapps.de>]

Graham Stark schrieb:
> On Jul 21, 12:27 am, rd <162...@gmail.com> wrote:
>> I'm playing around some with Ada, and today started with the
>> intent of cooking up a crappy mortgage calculator.  I did the
>> obvious:
>>
>>      type Money is delta 0.01 digits 12;
>>      package MIO is new Ada.Text_IO.Decimal_IO (Money); use MIO;


> I've been doing something similar. I would use float types if you can,
> not least because the root-finding algorithms you'll have to use
> probably won't work with discrete types. As someone else mentioned,
> financial institutions will have policies on exactly where and how
> money amounts are rounded, but it's unlikely you'll capture that just
> by relying on a Decimal type.


Also, consider using different types for different things,
e.g. Money for display, database tables, bank accounts, ... ,
and user defined floats or decimals for tax rates, and again
other (sub)types for interest rates and calculations reflecting
above mentioned policies.



--
Georg Bauhaus
Y A Time Drain  http://www.9toX.de