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Re: small integers, numerical efficiency
- To: firstname.lastname@example.org
- Subject: Re: small integers, numerical efficiency
- From: email@example.com (John Lewis)
- Date: Thu, 29 Oct 92 14:37:25 EST
I agree with the recent message by Jim Allard r.e. numerics in Lisp.
Lisp is wonderful, but both its design and its implementations
usually have a strong bias which hinders the use of the language
for numerical algorithms.
Bignums and rational numbers are (IMHO) useful for a relatively
specialized type of application- things like Macsyma.
These features are not generally used in what is probably
a much larger class of numerical algorithms.
David Moon (i recall) commented that he would rather see
floating point removed from Dylan than have a half-baked numeric
system like that in C. Although I agree that the C (also fortran,...)
numeric system is poorly designed, nevertheless in fact I would much
rather see Dylan have a "normal" but efficient numeric system
than Bignums!!! The numeric system in Scheme, which may be
considered to be well designed, drives me nuts!
For the current discussion I would like to try to label myself
as a 'non-AI' user of Lisp, the sort of programmer who will use Dylan.
In ~8 years of Lisp programming, I have
- used Lisp for languages and interactive code with excellent results
- used rational numbers only a couple of times
- never required bignums
- tried many wierd schemes to do efficient numeric work in a Lisp context
- still write most numerical code in C
Dylan is a rare opportunity; i also hope it does not inherit CL's numerical
inefficiencly and problems as described Jim Allard's message.
Acceptable efficiency is matter of opinion; I would find Dylan
acceptable for most uses if it were within 1/2-1/3 of the
speed of C/etc. implementations.
I am still looking forward to Dylan even if numerical efficiency is not
practical (the issues are way over my head certainly),
but I hope that at least an efficient and standard foreign function interface
can be provided.