Question

I don’t know what am I missing in the code?

set.seed(12345)
require(ggplot2)
AData <- data.frame(Glabel=LETTERS[1:7], A=rnorm(7, mean = 0, sd = 1), B=rnorm(7, mean = 0, sd = 1))
TData <- data.frame(Tlabel=LETTERS[11:20], A=rnorm(10, mean = 0, sd = 1), B=rnorm(10, mean = 0, sd = 1))
i <- 2
j <- 3
p <- ggplot(data=AData, aes(AData[, i], AData[, j])) + geom_point() + theme_bw()
p <- p + geom_text(aes(data=AData, label=Glabel), size=3, vjust=1.25, colour="black")
p <- p + geom_segment(data = TData, aes(xend = TData[ ,i], yend=TData[ ,j]),
                  x=0, y=0, colour="black",
                  arrow=arrow(angle=25, length=unit(0.25, "cm")))
p <- p + geom_text(data=TData, aes(label=Tlabel), size=3, vjust=1.35, colour="black")

Last line of the code produces the error. Please point me out how to figure out this problem. Thanks in advance.

Answer 1

I have no idea what you are trying to do, but the line that fails is the last line, because you haven’t mapped new x and y variables in the mapping. geom_text() needs x and y coords but you only provide the label argument, so ggplot takes x and y from p, which has only 7 rows of data whilst Tlabel is of length 10. That explains the error. I presume you mean to plot at x = A and y = B of TData? If so, this works:

p + geom_text(data=TData, mapping = aes(A, B, label=Tlabel), 
              size=3, vjust=1.35, colour="black")