R help - Mar 2011 - Changing colour of continuous time-series in ggplot2

Hi, 

This seems like there should be a simple answer, but having spent most of
the day trying to find it, I'm becoming less convinced and as such am asking
it here. 

Here's a sub-set of my data (a data.frame in R): 

myDF 
                                time     value      trial 
1   2011-03-01 01:00:00  64092  FALSE 
2   2011-03-01 02:00:00  47863  FALSE 
3   2011-03-01 03:00:00  43685  FALSE 
4   2011-03-01 04:00:00  44821   TRUE 
5   2011-03-01 05:00:00  48610   TRUE 
6   2011-03-01 06:00:00  44856   TRUE 
7   2011-03-01 07:00:00  55199   TRUE 
8   2011-03-01 08:00:00  69326  FALSE 
9   2011-03-01 09:00:00  84048  FALSE 
10 2011-03-01 10:00:00  81341  FALSE 
>From this, I can plot a simple time-series in ggplot: 
ggplot(myDF, aes(time,value)) + geom_line() 

but I'd like to change the colour of the line based on whether the trial
value is TRUE or FALSE, so I try: 

ggplot(myDF, aes(time,value)) + geom_line(aes(colour=trial)) 

but this draws a line from the value on row 3 to that on row 8 (essentially
plotting TRUE and FALSE as separate data-sets).  I've tried using various
other geometries (inc. geom_path()) but all have produced similar events. 
Is there a way I can plot the time-series in a continuous way (i.e. as one
data-set) and change only the colour of the line? 

Thanks, 
Joe


--
View this message in context:
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Sent from the R help mailing list archive at Nabble.com.

You need to specify the group aesthetic - that defines how
observations are grouped into instances of a geom.

Hadley

On Tue, Mar 15, 2011 at 8:37 AM, joeP <joseph.parrott at bt.com>
wrote:
> Hi,
>
> This seems like there should be a simple answer, but having spent most of
> the day trying to find it, I'm becoming less convinced and as such am
asking
> it here.
>
> Here's a sub-set of my data (a data.frame in R):
>
> myDF
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?time ? ? value ? ? ?trial
> 1 ? 2011-03-01 01:00:00 ?64092 ?FALSE
> 2 ? 2011-03-01 02:00:00 ?47863 ?FALSE
> 3 ? 2011-03-01 03:00:00 ?43685 ?FALSE
> 4 ? 2011-03-01 04:00:00 ?44821 ? TRUE
> 5 ? 2011-03-01 05:00:00 ?48610 ? TRUE
> 6 ? 2011-03-01 06:00:00 ?44856 ? TRUE
> 7 ? 2011-03-01 07:00:00 ?55199 ? TRUE
> 8 ? 2011-03-01 08:00:00 ?69326 ?FALSE
> 9 ? 2011-03-01 09:00:00 ?84048 ?FALSE
> 10 2011-03-01 10:00:00 ?81341 ?FALSE
>
> >From this, I can plot a simple time-series in ggplot:
>
> ggplot(myDF, aes(time,value)) + geom_line()
>
> but I'd like to change the colour of the line based on whether the
trial
> value is TRUE or FALSE, so I try:
>
> ggplot(myDF, aes(time,value)) + geom_line(aes(colour=trial))
>
> but this draws a line from the value on row 3 to that on row 8 (essentially
> plotting TRUE and FALSE as separate data-sets). ?I've tried using
various
> other geometries (inc. geom_path()) but all have produced similar events.
> Is there a way I can plot the time-series in a continuous way (i.e. as one
> data-set) and change only the colour of the line?
>
> Thanks,
> Joe
>
>
> --
> View this message in context:
http://r.789695.n4.nabble.com/Changing-colour-of-continuous-time-series-in-ggplot2-tp3356582p3356582.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>


-- 
Assistant Professor / Dobelman Family Junior Chair
Department of Statistics / Rice University
http://had.co.nz/