[R] ggplot "scale_x_date" : to plot quarterly scale?

[jpm miao]

Hi,

  I am plotting time series by  ggplot2, but I believe that my question
applies to other plotting tool as well.

  I want to make my x-axis the quarterly scale, e.g:
2000Q1 2000Q2.....

   However, scale_x_date and date_format("%m/%d") support all time formats
BUT QUARTERs........

library(scales) # to access breaks/formatting functions
dt + scale_x_date()
dt + scale_x_date(labels = date_format("%m/%d"))

   Is there any solution?

Thanks!

	[[alternative HTML version deleted]]