Re: [Gcl-devel] arrays

[Camm Maguire]

Greetings!

Vanuxem Grégory <address@hidden> writes:

> Le lundi 05 septembre 2005 à 13:42 +0200, Vanuxem Grégory a écrit :
> > Le dimanche 04 septembre 2005 à 23:38 -0400, Camm Maguire a écrit :
> > > Greetings!
> > > 
> > > What is '(array nil) suposed to mean?
> > > 
> > > I noticed that cmucl has support for 1 2 4 8 16 and 32bit array
> > > integers.  GCL has 1, 8, 16 and 32 (on 32bit machines).
> > 
> > Is it possible to send a 32 bits static array to cline ?
> > 
> > I have stopped my lapack implementation, since on my 64 bits machine,
> > arrays of int are array of long (8 bytes), and this will probably not
> > change in the future.
> 
> And if i use (on a 64 bit arch) :
> 
> (setq a (make-array  '(5 5) :element-type 'long-float :static t))
> (setq ipiv (make-array  5 :element-type '(signed-byte 32) :static t))
> 
> #(0 0 0 0 0)
> 
> >(dgetrf 5 5 a 5 ipiv)
> 
> 1
> 
> >ipiv
> 
> #(8589934593 17179869187 5 0 0)
>    ^^^^^^^^^ ^^^^^^^^^^^
> 
> the array contains '(signed-byte 64) even if that don't exist.
> 


OK, not sure what you men about 'not existing', but it is true that
the 64bit port has only 1,8,16,and 64 bit integer array support, and I
can see the need for a 32bit here as well.  Do you need a patch
against 2.6.7, or can you deal with the work-in-progress 2.7.0 from
cvs?

Take care,

> 
> 
> Cheers,
> 
> Greg
> 
> 
> > > 
> > > 1) Is there any real benefit to 2 and 4 bit integer types, considering
> > >    the access overhead vs space tradeoff?
> > > 2) My understanding is that the simple (signed-byte
> > >    2^n),(unsigned-byte 2^n) strategy will not pass all Paul's tests,
> > >    as upgraded-array-element-type must preserve subtypep relationships
> > >    -- one needs at least (unsigned-byte 2^n-1), etc.
> > >    I.e. non-negative-char, signed-char, and (optionally) (unsigned
> > >    char) for each size type.  This is what I've implemented at
> > >    present, and I'm passing all relevant tests.  I'd obviously like to
> > >    support the minimum number of types possible, if for no other
> > >    reason than it slows down subtypep et. al. on (array *).
> > > 
> > > Take care,
> > > 
> > 
> > 
> > 
> > 
> > _______________________________________________
> > Gcl-devel mailing list
> > address@hidden
> > http://lists.gnu.org/mailman/listinfo/gcl-devel
> > 
> 
> 
> 
> 
> _______________________________________________
> Gcl-devel mailing list
> address@hidden
> http://lists.gnu.org/mailman/listinfo/gcl-devel
> 
> 
> 

-- 
Camm Maguire                                            address@hidden
==========================================================================
"The earth is but one country, and mankind its citizens."  --  Baha'u'llah