(Ted Harding) <[EMAIL PROTECTED]> writes: > On 08-Nov-04 Duncan Murdoch wrote: > > Are you sure you're using the standard R choose()? I get different > > results from you: > > > >> print(choose(60000000000,1),digits=20) > > [1] 6e+10 ... > Well, that's good to learn! As usual, I'm out of date, but this > time it seems to matter: > > R-1.8.0 on Linux > > (Yes, it was the standard R choose() from that version). > > Perhaps I'd better roll up my sleeves and finally upgrade (though > I'm really waiting for the next release since the move to 2.0 seems > to have needed a few things ironed out).
And just to rub it in: > choose(60000000000,31) [1] 1.613121e+300 in 2.0.0, whereas the straightforward calculation > exp(lgamma(60000000000+1)-lgamma(60000000000-31+1)-lgamma(31+1)) [1] 1.613161e+300 is off in the 6th significant digit, due to cancellation between > lgamma(60000000000+1) [1] 1.429057e+12 and > lgamma(60000000000-31+1) [1] 1.429057e+12 (the true difference between the two is supposed to be > lchoose(60000000000,31)+lgamma(31+1) [1] 769.3459 ) -- O__ ---- Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
