Author: Carey
Date: 08:53:55 09/25/05
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On September 25, 2005 at 02:04:02, Robert Hyatt wrote: >Once someone told me "this is the cleanest-written chess program I have ever >seen written in FORTRAN." but then we started optimizing things for the Cray. If the code in Crafty is anything to go by, I'd say they were probably right. Crafty is written fairly cleanly, consistantly, lots of commnets, etc. I'm not a Fortran person, but over the years, I have run into more than a few programs that had way too many I, II, III, II1 type names. (And note the last one has a one...) It's almost like a rite of passage, to see how obscure you can make the variables and how many times you can use the letter 'I'. >It still was not _that_ bad after we finished, but some of the code looks very >strange for a non-cray programmer... I imagine it does. I've read some of your comments over the years about it. >I'll see what I can do. If I recall, it was about 30K lines of code, however, >so this is not going to be a quick and dirty deal. The variable names were >reasonable, although everything conformed to early FORTRAN standards (there was >no recursion, variable names were limited in length, or at least the first 6 or >8 letters (6 I think) had to be unique), etc. More when I get to the office The variables can't be as bad as what Larry Atkin used in Chess 0.5. I've studied that Pascal source, and the it's all 4 and 5 letter variables, and in most cases, only the last one or two are really significant. A few are a bit more descriptive, but they are the exception. If you get into his thought pattern, you can almost make sense of them, but it takes a bit of mind twisting to do it. A lot of it was just lifted from the Chess 4.5 code, of course, and you have to do those kinds of naming tricks for large assembly programs. But since Chess 0.5 was published for people to read, it would have been nice if he'd taken an hour and improved the names. >would also be interesting to see how fast it runs today, compared to speeds on >the old Cray hardware... I will add that the code was specifically modified in >several places to vectorize, but it ran like a dog on a non-vectorized box Who knows... Maybe somebody would get interested in seeing just how fast it can go and how it compares to Crafty, and they'll actually do all the work for you.... There are a lot of people in this group who are likely to be very curious about your old chess program!
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