> Date: Wed, 31 Mar 2004 15:38:43 -0700
> From: Neil Carlson <[log in to unmask]>
> On Wed, 2004-03-31 at 15:29, Robin wrote:
> > > Date: Tue, 30 Mar 2004 23:58:55 -0500 (EST)
> > > From: [log in to unmask]
> > > It would be a great convenience for such users if there were a "standard"
> > > means of interfacing to a generic binary computer, with two's complement
> > > integers, byte sized characters, 16, 32, and 64 bit integers and logicals, 32, 64, and
> > > 128(?)
> >
> > 80 is a common size.
>
> Not really, is it?
Yes it is. Whether you like it or not, the Intel 86 do arithmetic
using 80-bit f.p.
> x86 processors have internal 80 bit fp registers
> but anything that has to go out to memory gets truncated to 64 bits.
No it doesn't.
Single precision comes out as 32 bits, double precision at 64 bits,
and extended precision at 80 bits for those Fortran compilers that
support 80 bits.
> Since a high-level like Fortran can't/shouldn't make assumptions
> about where in the system a fp value is, an 80 bit kind really isn't
> feasible here. Are there systems that actually support 80 bit fp
> numbers fully?
> --
> Neil Carlson <[log in to unmask]>
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