. . .
Oleg's blew the heap at 847; mine valiantly struggled on 'til it blew the heap at 1910.
Hmm, I managed to compute bernoulli 2000 and even bernoulli 3000. The code is included. It took 7 minutes (2GHZ Pentium IV, 1GB memory) to compute bernoulli 2000 and 33 minutes for bernoulli 3000. I monitored the memory usage of the compiled application using top and found that the resident set stayed at 30MB, which is a little bit less than the resident set for Emacs. My emacs has a dozen of open windows, and has been running for a month. Just for the record, here's the result of bernoulli 3000:
(-2891939 ...6744 other digits... 81) % 12072109463901626300591430
Well, kudos to Oleg! I just ran his code from the msg this one replies to and got similar results: On a 650 Mhz Athlon with 128MB RAM I compiled with "ghc -O" (GHC 5.00.1). Using the "time" command, bernoulli 2000 took 490 sec. user time while bernoulli 3000 took 2170 sec. user time. Notice there were no heap overflows this time. I hope someone can explain the differences in space behavior between the version in Oleg's mail of March 6 and this version. I'm surprised we are as close as we are in time given that my processor is less than half as fast. I would also expect that my having 1/8-th the memory he has would slow me down more due to page faulting. The current version also fixes a minor glitch: the earlier version gave B_0 = 0 instead of 1. I think I got the right results for B_3000: My print-out had the same denominator along with a 6762-digit numerator with the same initial seven and final two digits. I don't get 6744 digits in the middle, however. I'm impressed by the good performance characteristics of high-level Haskell code. Nice work Oleg, -- Bill Wood wtwjek@winternet.com