[R] plot two graphs with different length of data

[Eric Hu]

Hi I am trying to plot two data set in the same picture window without
overlapping with each other. I am using the format plot(x1,y1,x2,y2)
but get the following error message:

>plot(as.numeric(r0[,4]),as.numeric(r0[,7]),as.numeric(r0[,4]),as.numeric(r0[,7][ind[,1]]))
Error in plot.window(xlim, ylim, log, asp, ...) :
        invalid 'ylim' value

Can anyone tell me what went wrong? Thanks.

Eric