Plotting fluctuation in R

I will try to be as less vague as possible. The below data set co开发者_StackOverflow中文版nsists of a device's power measurement and I have to plot a graph which would show the average fluctuation of the power (watt) during the Time column. I have to accomplish this in R but i really don't know which function or how should I do it as i'm a newbie to R. Any help will be highly appreciated!

Store No.,Date,Time,Watt

33,2011/09/26,09:11:01,0.0599E+03

34,2011/09/26,09:11:02,0.0597E+03

35,2011/09/26,09:11:03,0.0598E+03

36,2011/09/26,09:11:04,0.0596E+03

37,2011/09/26,09:11:05,0.0593E+03

38,2011/09/26,09:11:06,0.0595E+03

39,2011/09/26,09:11:07,0.0595E+03

40,2011/09/26,09:11:08,0.0595E+03

41,2011/09/26,09:11:09,0.0591E+03

rollapply in package:zoo will return a moving average (or a moving any-function). You can plot using points and then add a moving average line:

dat$D.time <- as.POSIXct(paste(dat$Date, dat$Time))
require(zoo)
 ?rollapply
 length(rollapply(dat$Watt,3, mean))
plot(dat$D.time, dat$Watt)
lines(dat$D.time[3:9], rollapply(dat$Watt,3, mean))