[R] Stacked barplot of timeseries data

[Demetri S. Mouratis]

Hi,

I'm trying to plot time-series data where each sample breaks down the  
percentage of CPU time spent in each of four states (usr, nice, sys,  
idle)


19:08:15  %usr  %nice   %sys   %idle
19:08:16    5      0     10     86
19:08:17   17      0     14     69
19:08:18    5      0      8     87
19:08:19   10      0     10     81
19:08:20    3      0      7     90
19:08:21    4      0      8     88
[on and on for many samples]

The plot I'm aiming for would stack the first three states in a  
colored barplot, so you get a visual sense of how busy the system is  
over the course of the day, and which state the CPU is spending its  
time in.  (I've done this as area charts as well).

barplot() looked promising, but it wants to stack the columns instead  
of the rows.

Anybody have a good solution for this?

Thanks!
...Demetri