AUDIT: r17421 - gnucash/trunk/lib/libqof/qof - Add a new function to the gnc_numeric library that converts denominators to exact powers of ten.

[Charles Day]

On Tue, Sep 16, 2008 at 10:54 AM, Charles Day <cedayiv at gmail.com> wrote:

> On Tue, Sep 16, 2008 at 9:38 AM, Andreas Köhler <andi5.py at gmx.net> wrote:
>
>> Hi,
>>
>> On Mon, 2008-09-01 at 22:09 +0200, Andreas Köhler wrote:
>> > Hi Charles,
>> >
>> > On Sun, 2008-07-27 at 11:33 -0400, Charles Day wrote:
>> > > Trac: http://svn.gnucash.org/trac/changeset/17421
>> > > Log:
>> > > Add a new function to the gnc_numeric library that converts
>> denominators to exact powers of ten.
>> >
>> > > Modified: gnucash/trunk/lib/libqof/qof/gnc-numeric.c
>> > > ===================================================================
>> > > --- gnucash/trunk/lib/libqof/qof/gnc-numeric.c      2008-07-27
>> 15:11:19 UTC (rev 17420)
>> > > +++ gnucash/trunk/lib/libqof/qof/gnc-numeric.c      2008-07-27
>> 15:33:23 UTC (rev 17421)
>> > > +  fraction = converted_val.denom;
>> > > +  if (fraction <= 0)
>> > > +    return FALSE;
>> >
>> > out of curiosity, what is the reason for disallowing negative
>> > denominators?  I am not sure whether there is a gnc_numeric API function
>> > to switch signs of nom and denom safely, but I am sure that doing it is
>> > possible :-) But maybe the current behavior is actually desired.
>>
>> I just noticed that ignoring negative denominators means that 1/(-10) is
>> now printed as "1 * 10", where it was printed as "10.00" before.  Is
>> that a regression we have to fix or not?
>>
>
> I can see how that would happen, because in previous versions, non-decimal
> fractions were forced to print in decimal form in some places. So even
> though the old routines considered 1/(-10) non-decimal, it would print it as
> decimal anyway. I think this takes us back to the original discussion.
> Should go ahead and add support for negative denominators to
> gnc_numeric_to_decimal()? I must only take less than 5 lines of code.
>

Here's the first attempt at that change. How are you testing these numbers?

$ svn diff
Index: gnc-numeric.c
===================================================================
--- gnc-numeric.c       (revision 17505)
+++ gnc-numeric.c       (working copy)
@@ -1043,7 +1043,14 @@

   converted_val = *a;
   if (converted_val.denom <= 0)
-    return FALSE;
+  {
+    converted_val = gnc_numeric_convert(converted_val, 1, GNC_DENOM_EXACT);
+    if (gnc_numeric_check(converted_val) != GNC_ERROR_OK)
+      return FALSE;
+    *a = converted_val;
+    *max_decimal_places = decimal_places;
+    return TRUE;
+  }

   /* Zero is easily converted. */
   if (converted_val.num == 0)


>
>
>> Ciao,
>> -- andi5
>>
>
> Cheers,
> Charles
>