[Numpy-discussion] please change mean to use dtype=float

[Travis Oliphant]

Charles R Harris wrote:
>
> Speed depends on the achitecture. Float is a trifle slower than double 
> on my Athlon64, but faster on PPC750. I don't know about other 
> machines. I think there is a good argument for accumlating in double 
> and converting to float for output if required.

Yes there is.  It's just not what NumPy ever does so it would be an 
exception in this case and would need  a more convincing argument in my 
opinion.    You can always specify the accumulation type yourself with 
the dtype argument.  We are only talking about what the default should 
be.  

-Travis