leading superscript in plotmath expression (w/ggplot2)

ggplot2, plotmath, r

Solution

How about this:

ggplot(mtcars, aes(x=disp, y=mpg)) + 
  geom_point() +
  ylab(expression(phantom(0)^y * x))

I was certain there must be a way to do a "placeholder" character, but I had to scroll down a bit in `?plotmath` to find it.

Problem

I'd like to use `plotmath` to create an axis containing a leading superscript in a `ggplot2` plot. Creating superscripts on axis labels works nicely, like so: ``` require(ggplot2) ggplot(mtcars, aes(x=disp, y=mpg)) + geom_point() + ylab(expression(x[y])) ``` However, I'd like to have my axis label read "y(superscript)x" - logically that would be `^yx`, but that won't parse: ``` Error: unexpected '^' in: " geom_point() + ylab(expression(^" ``` Is there a way to force a superscript at the beginning of a statement?

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