[Numpy-discussion] Removing datetime support for 1.4.x series ?

[Travis Oliphant]

On Feb 2, 2010, at 8:53 PM, David Cournapeau wrote:

> Travis Oliphant wrote:
>
>> I think we just signal the breakage in 1.4.1 and move forward.   The
>> datetime is useful as a place-holder for data.  Math on date-time  
>> arrays
>> just doesn't work yet.    I don't think removing it is the right
>> approach.    It would be better to spend the time on fleshing out the
>> ufuncs and conversion functions for date-time support.
>
> Just so that there is no confusion: it is only about removing it for
> 1.4.x, not about removing datetime altogether. It seems that  
> datetime in
> 1.4.x has few users, whereas breaking ABI is a nuisance for many more
> people. In particular, people who update NumPy 1.4.0 cannot use  
> scipy or
> matplotlib unless they build it by themselves as well - we are talking
> about thousand of people at least assuming sourceforge numbers are  
> accurate.
>
> More fundamentally though, what is your opinion about ABI ? Am I right
> to understand you don't consider is as significant ?

I consider ABI a very significant think.  We should be very accurate  
about when a re-compile is required.    I just don't believe that we  
should be promising ABI compatibility at .X releases.   I never had  
that intention.  I don't remember when it crept in to the ethos.

The ABI will change at some point.    Having it change at 1.X releases  
seems reasonable (it certainly was my thought when 1.0 came out).   
Yes, it means distributors of packages that depend on NumPy will have  
to recompile against the new version, and I can see why some might  
want to avoid that.  Pushing what is really a distribution problem  
back to the NumPy package to manage separately is not the approach I  
would take.

In my opinion, we should fix the problems that exist by changing the  
ABI number of NumPy 1.4.x to accurately reflect that a re-build of  
NumPy is necessary, and then spend time building SciPy and matplotlib  
binaries against it.

If there is also a desire to make another release of NumPy 1.3.X which  
removes the date-time additions, but incorporates the other fixes, and  
somebody wants to spend the time doing that, then great.

-Travis