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Re: floating-point efficiency: Lisp vs. Fortran

In article <...> hmadorf@eso.org writes:
 > This does not at all agree with my recent observations. I carried
 > out the following simple floating-point benchmark: I coded the 
 > log-factorial function in Fortran-77 and in Lisp (using a simple 
 > do-loop). The algorithm simply sums up all the log-terms. (The code
 > is available on request.) I executed the code using
 > [...] 
 > Two versions of the CL code were tested, one without declarations,
 > the other fully spiced with declarations. The CL-code was compiled
 > with (speed 3) optimization. The Fortran code was not particularly
 > optimized. My observations:

Did you also declare (safety 0) in the optimizations?  I don't know
about MCL, but in some lisps the safety settings often take precedence
over the speed settings, so type checking and dispatch may be left in
even at high speed settings.


Thomas A. Russ                                             tar@isi.edu    
USC/ISI, 4676 Admiralty Way, Marina del Rey, CA 90292      (310) 822-1511