Message from discussion how to declare doubles in f95
Subject: Re: how to declare doubles in f95
Date: Thu, 29 Jan 2009 18:58:43 +0000 (GMT)
Organization: University of Cambridge
References: <firstname.lastname@example.org> <ron-shepard-D7D3BE.email@example.com> <firstname.lastname@example.org> <ron-shepard-1EBB22.email@example.com>
In article <ron-shepard-1EBB22.12392629012...@news60.forteinc.com>,
Ron Shepard <ron-shep...@NOSPAM.comcast.net> wrote:
>> "Many"? And "common"? Not really. The only ones that I can think
>> of were CDCs and Crays, all of which were extremely specialised
>> supercomputers that sold in very small numbers. What else were you
>> thinking of?
>There were also the fortran programmable attached processors that were
>fairly common in the 80's. These included the FPS-164 and FPS-264
>machines which I used. Certainly if you count every computational
>scientist and engineer who used a CDC, Cray, ETA, SCS, or one of these
>attached processors in the 80's, you would get a high percentage,
>probably over 90% of us. Not only were these machines sold to
>individual groups and local departments, but there was also a number of
>national supercomputer centers (NSF, DOE, DoD) which gave access to
>almost everyone who applied. If that >90% estimate is correct, then
>"common" would be the correct description, right? My feeling is that
>scientists in the UK (your address) had wide access to these kinds of
>machines earlier than they did here in the US.
90% of who?
Most of the coprocessor compilers I saw took a 'conventional' view
of precision, but I didn't see many as those coprocessors never
really took off.
>> Ones using 48 bits for single and 96 for double were probably more
>> common. Once upon a time ....
>On the other hand, I don't know anyone who used a machine like this. I
>think Harris computers used 3-byte and 6-byte data, which is almost what
>you are claiming, but I think there were fewer of these machines than
>the types described above, and they were almost certainly less commonly
>used. There were no national supercomputer centers based on Harris
>computers, for example. I personally never used one, but I exchanged
>code with collaborators who did, and wrestled with their integer*3 and
The ICL 1900 range was perhaps the main one, but nowhere near the only
one. I think it took that word size from Ferranti.