From 7103522044078317099 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: f78e5,d6b00896947ca26f X-Google-Attributes: gidf78e5,public From: David Vandevoorde Subject: Re: matrix based on Date: 1997/05/18 Message-ID: <337DED05.15E4@vandevoorde.com>#1/1 X-Deja-AN: 242200045 References: <5lc577$57i@netlab.cs.rpi.edu> <5lgu87$d15@netlab.cs.rpi.edu> X-Original-Date: Sat, 17 May 1997 13:38:13 -0400 Organization: - X-Auth: PGPMoose V1.1 PGP comp.std.c++ iQBFAgUBM36wx+EDnX0m9pzZAQFl5gF8CB9cBpsezRFNZqjBkpuuVVdsc5Mw/buw LS68QJSiRX/bpXw44aPIARDfcsmgqLTp =diEP Reply-To: daveed@vandevoorde.com Newsgroups: comp.std.c++ Originator: fjh@mundook.cs.mu.OZ.AU Oleg Zabluda wrote: [...] > I think I've posted this though already, but let me rehash it again. > Valarray was not supposed IMHO to be a building block for > vector/matrix classes. It was probably just an attempt to provide an > abstraction for vector/parallel computer architectures. As I recall, the original valarray proposal paper _did_ target valarray (numarray) as a building block for matrix and vector classes (but not _only_ for this purposes). Although I don't think that abtraction of parallel architectures was the primary motivation, the interface certainly looks like data-parallelism was intended to be exploited where possible. > C gained such an incredible popularity IMHO solely because it provided > good implementation of the just right "hardware platform" abstraction. > I think it's extremely important that C++ continues developing this > trend. Whether valarray is a correct implementation of the correct > abstraction, I don't really know. Seems to be so, but unless I or the > C++ community have more experience with it, it's hard for me to tell. My opinion differs here (i.e., I think the valarray abtraction is not a good one). > Maybe it's a correct abstraction of a single parallel/vector CPU, but > the wrong abstraction of the multiple symmetric or massively parallel > "hardware platform". Who knows. If it is not, I think that DRASTIC > measures have to be taken IMMEDIATELY. I wouldn't mind a standard without valarrays, but I don't think they are truly a problem from an uninterested user's perspective. It's too late to replace them, but they don't impact other library aspects. We can just ignore that part of the library. Daveed --- [ comp.std.c++ is moderated. To submit articles: try just posting with ] [ your news-reader. If that fails, use mailto:std-c++@ncar.ucar.edu ] [ FAQ: http://reality.sgi.com/employees/austern_mti/std-c++/faq.html ] [ Policy: http://reality.sgi.com/employees/austern_mti/std-c++/policy.html ] [ Comments? mailto:std-c++-request@ncar.ucar.edu ]