[R] slowness of plot(x, type='l')

[ronggui]

On Fri, 06 May 2005 15:19:01 -0500
apjaworski at mmm.com wrote:

> 
> 
> 
> 
> A couple of days ago a few messages indicated that something changed in the
> basic plot routine that made plot(*, type='l') slow for large data sets.
> Some people even reported crashes for very large data sets.  As far as I
> remember, this was not reported as a formal bug.
> 
> I am still not sure if this is a bug, so I report my findings here.  First
> of all, I think I see a slowdown of the plot function, although I do not
> have older versions of R installed, so I cannot do side-by-side
> comparisons.  Secondly, I noticed that the behavior of plot(*, type='l')
> differs.  Before R-2.1, the plotted lines would appear on the plot
> gradually.  Now, after the wait, the whole plot appears at once.
> 
> Here are my timing results.  I am on Windows2000, IBM Intellistation with
> Xenon 2.8MHz with 1Gb of memory.  I checked May-06 versions of R-patched
> and R-devel built from sources.  I ran the following simple test:
> 
> x <- rnorm(n)
> date(); plot(x, type='l'); date()
> 
> Here are the timings:
> 
>       n     seconds
>       5000  1
>       6000  2
>       7000  4
>       8000  6
>       9000  9
>       10000 13
>       12000 22
>       14000 36
>       20000 91
~~~~~~~~~~~~~~~~~~~~~~~
I have no such porblem,my OS is debian,256M ram and 2Gswap.

> x <- rnorm(200000)
> date(); plot(x, type='l'); date()
[1] "Sat May  7 08:49:18 2005"
[1] "Sat May  7 08:49:20 2005"
> version
         _
platform i386-pc-linux-gnu
arch     i386
os       linux-gnu
system   i386, linux-gnu
status
major    2
minor    1.0
year     2005
month    04
day      18
language R


> It looks like only type='l' and type='o' exhibit this behavior.  All other
> types produce plots in approximately 1 second.  Also, the (long) wait and
> plot at once behavior happens with the two types mentioned.  All others
> (except 'n' of course) produce gradually appearing plots.
> 
> Hope this helps,
> 
> Andy
> 
> __________________________________
> Andy Jaworski
> 518-1-01
> Process Laboratory
> 3M Corporate Research Laboratory
> -----
> E-mail: apjaworski at mmm.com
> Tel:  (651) 733-6092
> Fax:  (651) 736-3122
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html