Newsgroups: comp.lang.c
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: fortran to C converter
Message-ID: <1989Apr24.172747.993@utzoo.uucp>
Organization: U of Toronto Zoology
References: <10176@socslgw.csl.sony.JUNET> <12247@lanl.gov>
Date: Mon, 24 Apr 89 17:27:47 GMT

In article <12247@lanl.gov> jlg@lanl.gov (Jim Giles) writes:
>On the Cray, doubles have 28 digits of precision, but it takes 50 (that's
>right - FIFTY) time as long to compute with doubles as with singles.  That
>doesn't even include the fact that doubles don't vectorize!  Single precision
>carries 14 digits of precision and is adequate for most computation.  The
>use of double should be for very rare cases in which single precision isn't
>sufficient.

Given the pervasive nature of double in C code, sounds like Cray made a bad
decision (or an interim one).  The right way to do this is to make float and
double synonymous (which is legal) and use ANSI C's "long double" for the
super-precise type.
-- 
Mars in 1980s:  USSR, 2 tries, |     Henry Spencer at U of Toronto Zoology
2 failures; USA, 0 tries.      | uunet!attcan!utzoo!henry henry@zoo.toronto.edu