performance of apply

[Bill Simpson]

I was computing a function f(u,v) on bivariate point process data of
about 4500 points. The computation in R took about 96 hours (4 days!) on a
Pentium Pro 200 under linux with little or no other load. So I think speed
can be an issue, esp. when computing things one will eventually display
with image().

My collaborator and I wound up coding it in C and now the computation
takes 4 min (yes, 4 min vs 4 days).

Probably it could have been sped up in R but that would have taken the
same effort as coding in C, and the result would have been slower.

Bill Simpson

-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To: r-devel-request@stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._