fix the test case; it really is an overflow on division, there's a

[Linas Vepstas]

On Sat, Jun 26, 2004 at 07:30:46PM -0400, Derek Atkins was heard to remark:
> Linas Vepstas <linas at cvs.gnucash.org> writes:
> 
> > fix the test case; it really is an overflow on division, 
> > there's a bunch of huge prime numbers involved.
> 
> Unfortunately this test-case actually came from test-query..  It had
> created a random transaction that happened to have those two values as
> the amount and value and was trying to compute the shareprice.

I'm trying to fix the make-random-transaction so that it won't gen
insane data. Harder done than said.

> Could you please explain exactly what a division overflow means?

if x=a/b and y =c/d  then x/y = (a*d)/(b*c)  If, after eliminating
all common factors from the above, the if the numerator and/or
denominator are *still* greater than 2^63 then its an overflow.

> If this test-case really is going to over-flow on this operation then
> we need to fix all the other tests to make "reasonable" random
> gnc-numerics.  Go run 'test-query' and watch it fail consistently

Yes. 

--linas

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