Code:
d1 <- structure(list(x1 = c(31.7858,25.8623,23.7758,30.1564,28.179,25.3966,31.5879,40.3233,28.8774,27.4434,37.6055,38.2847,40.5864,38.586,32.5489,38.2273,45.6876,52.3452,42.6654,49.8273), y1 = c(3.62,2.38,1.98,2.71,2.25,2.37,2.28,2.30,3.06,2.22,2.66,2.83,4.16,2.83,3.10,3.00,4.52,5.61,3.95,6.45)), .Names = c("x1", "y1"), class = "data.frame", row.names = c(NA,
-20L))
d2 <- structure(list(x2 = c(22.5824,17.8283,21.4613,20.0485,24.5318,23.0919,23.3925,27.2867,23.7026,23.7338,25.4886,26.7058,25.6673,24.991,25.2346,18.7816,26.2372,25.9479,25.819,25.1697), y2 = c(2.12,1.55,1.65,1.52,1.80,1.77,1.68,1.46,2.05,1.63,1.59,1.85,2.53,1.98,2.32,1.66,2.09,2.51,2.25,2.54)), .Names = c("x2", "y2"), class = "data.frame", row.names = c(NA, -20L))
library(reshape2)
library(ggplot2)
names(d2) <- c("x1", "y2")
df <- rbind(melt(d1, id.vars = "x1"), melt(d2, id.vars = "x1"))
ggplot(df, aes(x1, y = value, colour = variable)) +
geom_point() + labs(x = "x", y = "y") +
scale_colour_manual(values = c("red", "blue"), labels = c("d1", "d2"))
