On Tue, Feb 12, 2013 at 4:17 PM, Pedro Giffuni <p...@apache.org> wrote: > Ugh.. > > I haven't been following this thread at all ... >
I recommend reading the archives then, since every argument that could be made, has been made already. -Rob > I unsubscribed from the -dev list because I always ended up in absurd > discussions > and there was not much technical content either. > > I suspected it would be bikeshed.org material but in any case let me make > things clear. > > - 0^0 = 1 is NOT mathematically correct. The limit of x^x when x tends to +0 > is 1, > however when you consider the limit when x tends to -0, the limit is > infinite. This > is called Indeterminate Form. > http://en.wikipedia.org/wiki/Indeterminate_form > > > If you wonder, I failed a math quiz in the University for blindly using the > value my > HP Calculator gave (1), so I am sort of glad that this has been a free > educational > experience for some of you. > > The implementation in OOo doesn't return explicitly a 1 value but instead > relies on > what the libc pow() function does. The standard libc lets you do 0^0 but it > also lets > you divide by zero without aborting . Modern IEEE 754 2008 implements three > power functions pow(), pown() and powr(), powr() being the most similar to > the real > mathematical function. > > The implementation is non intrusive: I added a wrapper in SAL that behaves > like > powr() so that we don't affect other formulas that use pow() internally. So > far > no one has given an example where shooting yourself in the foot by expecting > pow(0,0) to be 1 is a good thing. > > I am gladly surprised that Excel does the same, but the real reason why I went > ahead and implemented a solution is to do the right thing, mathematically > speaking. Mathematical correctness is not something that IMHO pertains to > democracy. > > Sure it would be nice to have an option to adjust your results for > mathematically undetermined cases like 0^0 or 0/0 but unless you are planning > to implement it don't expected such features to appear magically either. > > I would be extremely disappointed to have to revert a correct fix for > non-technical > reasons. I think I would lose any motivation to improve other functions in > Calc. > > Pedro.
