Long-float variant giving more precision to numerical computations.

Douglas Crosher wrote:
> Hello Ray,
> 
> The changes have been committed, except for the changes to the Fortran 
> code.  Patches
> to the Fortran code are temporarily available here:
> 
> Patches to use long-float (SCL, CLISP):
> http://www.scieneer.com/files/maxima-lf-patch1.txt.gz
> 
> Patches to use CMU CL double-double-float:
> http://www.scieneer.com/files/maxima-ddf-patch1.txt.gz
> 
> The CLISP version is working relatively well.  The CMUCL double-double 
> float version has
> some problems that have not been explored yet but can be reproduced with 
> the above patch.

I haven't tried the above patch, but I did enable double-double support 
in maxima.  plot.lisp doesn't even compile on sparc.  This is because 
most-positive-flonum is really too big.  It can be presented but you 
can't multiply or divide it.  It's an artifact of how multiplication and 
division is done on double-doubles.

A quick fix for that, and everything compiles.  I have to say it is 
rather nice to see all those extra digits.  There are a few issues 
though.  Printing large floats doesn't print out all the digits.  sin 
only returns double-float numbers.

And, of course, a huge number of tests fail.

Ray