----- Original Message -----
From: sen1 at math.msu.edu
Date: Saturday, August 4, 2007 1:47 pm
Subject: Re: [Maxima] stuff not in 5.13 branch
> One thing I (and I think other users) would very much like to see
> is a
> global key which transparently turns on and off arbitrary
> precision. I realize that this may require redoing some intrinsic
> functions, so it may take time to do. Are any of the current lisps
> set up to do this?
There is a "generic arithmetic" package that I've posted that would allow fairly transparent use of bigfloats from lisp, but "setting a global key" is not a workable approach.
Declaring something to be a bigfloat is, so far as I can tell, entirely without any effect. If you want a number that is produced somewhere to become a bigfloat, multiply it by 1.0b0.
Square root should not be a problem, unless perhaps you are expecting a complex or imaginary result.
><snip>
>
> The documentation of Maple and Mathematica state that they allows
> whole sessions which work transparently with arbitrary precision,
> but I have not
> tried them to see if similar problems exist in those packages.
I would say that this is pretty much of a lie, if you expect something that works with single machine float to work the same way (transparently) with arbitrary precision.
If you expect that you can do a computation in, say, 100 decimal digits of "arbitrary" precision and then transparently do it in say, 200 decimal digits, then the algorithm is more likely to be transparently the same.
RJF
>