ggplot, getting two scales and one stat.

I have a simple plot:

ggplot(polls, aes(x =Date, y = Popular_Support, colour=Party, shape=Source))
+
stat_smooth(span=0.5) +
geom_point()

How can I get the smooth to only render along one of the scales? ie, I want
to see regressions for each colour, but not each shape.

Thanks Hadley, unfortunately doing this gives me an error:

ggplot(polls, aes(x =Date, y = Popular_Support, colour=Party)) +

+ stat_smooth(span=0.5) +
+ geom_point(aes(shape=Source))
Error in `[.data.frame`(df, , var) : undefined columns selected

if I move it back up into ggplot, then it works fine.... ??



2008/9/27 hadley wickham <h.wickham at gmail.com>

On Sat, Sep 27, 2008 at 1:08 AM, Tylere Couture <tylerecouture at gmail.com>
wrote:

I have a simple plot:

ggplot(polls, aes(x =Date, y = Popular_Support, colour=Party,
shape=Source))
+
stat_smooth(span=0.5) +
geom_point()

How can I get the smooth to only render along one of the scales? ie, I
want
to see regressions for each colour, but not each shape.

Just map shape to source only for the points:

ggplot(polls, aes(x =Date, y = Popular_Support, colour=Party)) +
stat_smooth(span=0.5) +
geom_point(aes(shape=Source))

Hadley

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