Adding Additional Y-Axis in R with ggplot2 -

let's have following (x0,y0) data have plotted (the y0-axis plotted on left-hand side):

x0,y0 ----- 500,1 200,3 ... 

further, have set of data (x1,y1) given as:

x1 y1 ----- 1.5,1 3.2,2 ... 

i wanting add addition y1-axis on right-hand side, have x1 break points , y1 labels. x1 , y0 on same scale, 2 datasets of different lengths, , there no formula 1 can use derive x1 y0.

thanks

it's not entirely clear you're looking for. this?

df1 <- data_frame(x0 = c(500, 300),               y0 = c(1, 3))  df2 <- data_frame(x1 = c(1.5, 3.2),                   y1 = c(1, 2))  ggplot(df1, aes(x0, y0)) + geom_point() +    scale_y_continuous(expand = c(0.5,0.5),                      sec.axis = sec_axis(trans = . ~ .,                                           breaks = df2$x1, labels = df2$y1))