Rotate X Axis Labels of twoord.plot in R

I am using the twoord.plot function in the plotrix package and need to rotate 开发者_StackOverflowthe X Axis tick labels 45 degrees. Anyone know how to do so?

You need to suppress the usual labeling and put your desired labeling in with text(..., srt=45). Since by default text only goes in the plot region, the y argument may need to be negative, and you will need to extend the plotting region by "lowering" the third argument to usr. This is all described in the R-FAQ.