[R] ggplot add a legend?

[Ista Zahn]

Map year to an aesthetic and let ggplot do it for you:

df2010$year <- 2010
df2011$year <- 2011
df2012$year <- 2012
dfAll <- rbind(df2010, df2011, df2010)

ggplot(dfAll, aes(x=Price, y=percenCapacity, color=year) +
scale_x_log10()

Best,
Ista

On Mon, Dec 17, 2012 at 6:03 PM, jcrosbie <james at crosb.ie> wrote:
>
> How to I go about adding a legend  to the following plot?
>
> ggplot() +  geom_line(aes(x=df2010$Price,y=df2010$percentCapacity), colour =
> "red")
> + geom_line(aes(x=df2011$Price,y=df2011$percentCapacity), colour = "green")
> +geom_line(aes(x=df2012$Price,y=df2012$percentCapacity), colour = "blue")
> +scale_x_log10()
>
>
> <http://r.789695.n4.nabble.com/file/n4653389/Rplot01.jpeg>
>
>
>
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