Proposal for modifying gnucash to use exact quantities

John Hasler
25 Jul 2000 12:45:49 -0500

Buddha Buck writes:
> I know that the local gas pumps do accurately treat the $1.699/gallon
> price as $1.699/gallon -- when I buy 10.000 gallons, I pay $16.99, not
> $17.00.

And when you buy 11.000 gallons you will be billed $18.69 (or maybe
$18.68), not $18.689.

> The pump evidentially knows about mills.

The pump knows that 1.699 * gallons = total sale, anyway.  The pump (or
the cash register, or the clerk) will round the sale to the penny and the
station's accounting software will never see the mills.

IMHO transaction_total != price * quantity.

Rather, transaction_total = f(price, quantity)
where transaction_tatal is an integer, price and quantity are reals, and
f() is a nonlinear (though usually monotonic) function.  transaction_total
is the amount that you are obligated to pay or have the right to receive,
and it is what the accountants want us to keep exact track of.

Quantity is an inventory control matter and not expected to be exact.
Price and f() are part of your contract with the other party and so are
legal matters.  Only transaction_total is really accounting.
John Hasler (John Hasler)
Dancing Horse Hill
Elmwood, WI