pure-lang-users

Re: [pure-lang-users] C macros

[Albert G. <Dr....@t-...>]

Eddie Rucker wrote:
> The only thing missing from Pure types is rationals.

Well, you can always map these to doubles when passing them to GSL.

-- 
Dr. Albert Gr"af
Dept. of Music-Informatics, University of Mainz, Germany
Email:  Dr....@t-..., ag...@mu...
WWW:    http://www.musikinformatik.uni-mainz.de/ag

Re: [pure-lang-users] C macros

[Eddie R. <er...@bm...>]

On Tue, 2008-08-26 at 18:32 +0200, Albert Graef wrote:
> Eddie Rucker wrote:
> > The only thing missing from Pure types is rationals.
> 
> Well, you can always map these to doubles when passing them to GSL.
> 

Agreed. Most of the time doubles or complex values is what many would
want anyway. I might use integers for neural networks (but not with
fuzzy values) or Number theory stuff so integers, double, and double
complex seem to be the best ones to implement. By the way, some matrices
with rational numbers can be rewritten to equivalent matrices with
integers. 

Example:
1/2x+5/6y=5/2
2/3x-1/2y=4

multiply both equations through by 6 ==>

3x+5y=15
4x-3y=24

e.r.

Re: [pure-lang-users] C macros

[Albert G. <Dr....@t-...>]

Sorry for the repeated posts. Looks like this message took a long detour 
to Mars or whatever.

-- 
Dr. Albert Gr"af
Dept. of Music-Informatics, University of Mainz, Germany
Email:  Dr....@t-..., ag...@mu...
WWW:    http://www.musikinformatik.uni-mainz.de/ag

Re: [pure-lang-users] C macros

[Eddie R. <er...@bm...>]

On Tue, 2008-08-26 at 02:54 +0200, Albert Graef wrote:
> - Accessing the fields of a struct through pointers in Pure is possible 
> (see the stuff at the end of primitives.pure), but probably 
> non-portable. You'd probably need some getter/setter functions in your 
> wrapper to do that in a safe way.

Um... Is there some way from Pure to find out the byte sizeof ints,
doubles, complex, etc? When the sizes change on different machines
and/or compilers I'd like the library to automatically handle this.

e.r.

Re: [pure-lang-users] C macros

[Albert G. <Dr....@t-...>]

Eddie Rucker wrote:
> Um... Is there some way from Pure to find out the byte sizeof ints,
> doubles, complex, etc? When the sizes change on different machines
> and/or compilers I'd like the library to automatically handle this.

You can put some C functions for that in your wrapper, too. (On 
non-antique hardware, double should always be 64 bit, int 32; the latter 
might be aligned on 8 byte boundaries on some 64 bit systems, though.)

Albert

-- 
Dr. Albert Gr"af
Dept. of Music-Informatics, University of Mainz, Germany
Email:  Dr....@t-..., ag...@mu...
WWW:    http://www.musikinformatik.uni-mainz.de/ag

Re: [pure-lang-users] C macros

[Eddie R. <er...@bm...>]

On Wed, 2008-08-27 at 17:21 +0200, Albert Graef wrote:
> Eddie Rucker wrote:
> > Um... Is there some way from Pure to find out the byte sizeof ints,
> > doubles, complex, etc? When the sizes change on different machines
> > and/or compilers I'd like the library to automatically handle this.
> 
> You can put some C functions for that in your wrapper, too. (On 
> non-antique hardware, double should always be 64 bit, int 32; the latter 
> might be aligned on 8 byte boundaries on some 64 bit systems, though.)

Exactly, on my Linux box (64bit) I have 8 byte boundaries and on my Windows box (32bit) I have 4 byte boundaries.
Can I always determine if a system is 32bit or 64bit from sysinfo?

e.r.