[Numpy-discussion] Re: Numpy-discussion digest, Vol 1 #693 - 3 msgs
verveer at embl-heidelberg.de
Thu Sep 4 01:55:03 EDT 2003
> 1. Add a type parameter to sum which defaults to widest type.
> 2. Add a type parameter to reductions (and fix output type handling).
> Default is same-type as it is now. No major changes to C-code.
> 3. Add a WidestType(array) function:
> Bool --> Bool
> Int8,Int16,Int32,Int64 --> Int64
> UInt8, UInt16,UInt32,UInt64 --> UInt64 (Int64 on win32)
> Float32, Float64 --> Float64
> Complex32, Complex64 --> Complex64
This sounds like a good solution.
> The only thing this really leaves out, is a higher performance
> implementation of sum/mean which Peter referred to a few times.
Is this really the case? It depends on how you plan to implement the output
conversion. If you will do this by allocating a temporary converted copy of
the complete input before the calculations then this potentially requires a
lot of temporary storage. But it is certainly possible to come up with an
implementation that avoids this. Have you given this some thought?
> if you want to write a specialized module, we'd be happy to put it in
> the add-ons package.
I hope that the reduce methods can be made sufficiently efficient so that this
will not be necessary.
More information about the NumPy-Discussion