Re: New Math Coprocessor - who has a need for it???

[dempson@swell.actrix.gen.nz (David Empson)]

In article <1993Jul14.200342.18140@ifi.unizh.ch> gudat@avalon.physik.unizh.ch (gudat henrik) writes:
>
> > So would this card speed up _ALL_ programs written
> > with Orca/C for example?
>  
> Yes, if they have been compiled with the "#pragma float..." command.

Not quite true.  An ORCA/C or Pascal program that uses floating point
numbers will run faster with a NC installed, but only if the SANE
patches have been installed, or the program uses the #pragma float
option (which tells ORCA/C to call the card directly).  Direct calls
are faster, but there will still be a significant improvement if the
program is calling SANE.

There will be no difference to the speed of a program which doesn't
use floating point numbers.

> > Doesn't Orca/C use SANE for all math?
>  
> Most probably it does, yep. Programs written in high-level languages
> tend to use floating point stuff way too often.

This is a major overstatement.

ORCA/C and Pascal programs will only use SANE for expressions involving
floating point numbers (i.e. float, double, extended or comp variables
for ORCA/C, or Real, Double, or Extended for ORCA/Pascal).

Expressions involving only integers and/or long integers will be
performed using direct code or library routines, and no floating point
calculations.  A program containing no floating point variables and no
expressions involving floating point quantities will not use SANE
(other than starting it up and shutting it down).

> The patches have been originally written for the FPE, but they work
> equally well with the NC. I also saw a patch for AppleWorks Classic,
> but I don't know if it works with the NC. Theoretically there is no
> reason to assume it wouldn't, but I'd like to check it out first.

If the card is hardware interface compatible with the FPE (and it
sounds like it is, since the FPE's SANE patches and ORCA code will
support it), then the AppleWorks Classic patch should certainly work
with the NC.  This will improve the speed of the AppleWorks
Spreadsheet (and possibly report generation in the Database) but won't
affect much else.
-- 
David Empson                                                               
dempson@swell.actrix.gen.nz                                                
Snail mail: P.O. Box 27-103, Wellington, New Zealand