[R] R performance on Unix

[Jason Turner]

morozov wrote:

> Hi
> I'm observing a huge difference in the performance speed of R on Windows and 
> Unix, even though I know that my Unix machine is much more powerful than my 
> Win machine. 
> In particular, any character processing task is very time consuming on Unix.
> 
> strptime(x,"%H:%M:%S") is about 10 times slower on Unix for vector x of the 
> length of ~ 500. read.table() also is very slow. is there any way to speed up 
> these ?
> 

As was pointed out, the strptime issue sounds like a C-library problem 
on your machine.  The text processing might be the same.  Is this a 
development version of a Un*x OS?  What's the output of uname -a?  Is it 
a source or binary build of R?  If binary, try building and installing 
from source (provided you've got the disk space, you can do this, even 
if you're not root).  Is the problem apparent on other boxen with 
similar OSs (ie is it hardware)?

If you absolutely must continue to use that box and OS and R build, 
read.table() can be sped up using the colClasses argument (R doesn't 
have to guess what class each column should be), but it sounds like a 
problematic installation.

Cheers

Jason
-- 
Indigo Industrial Controls Ltd.
http://www.indigoindustrial.co.nz
64-21-343-545
jasont at indigoindustrial.co.nz