geom_line() doesn't work

[bw12]

Hi!
I have a problem with geom_line(), when I use it, it doesn't work. I can use goem_point or else but this one does not work, what can I do? Is there something else I can try?

Thank you a lot.

[FJCC]

Here is a simple example of using geom_line that works for me. Does it work for you? Can you provide an example that does not work for you?

library(ggplot2)
DF <- data.frame(Xval = 1:5, Yval = 11:15)
ggplot(DF, aes(Xval, Yval))  + geom_line()

[bw12]

I created the data frame with values on y and word on x as:
a <- data.frame(words, values, lettersAsFactors=TRUE)
then I write:
ggplot(data = a, aes(x = words, y = values))+ geom_point() + geom_line() + NULL
when I run this it only draw the points and not the line...I do not know why.

[colt1313]

You might want to try creating the line first and then adding the points afterwards. You could also try leaving out the NULL you added at the end.

[Jwvz001]

@bw12

lettersAsFactors=TRUE

Because you are using factors, which is different from @FJCC 's numeric vars. From what I understand from the documentary, geom_line() attempts to draw a line at each factor level. Specifying that they all belong to the same group does the trick.

Does the code below solve your problem?

DF <- data.frame(Xval = as_factor(LETTERS[1:5]), Yval = 11:15)               
ggplot(DF, aes(x = Xval, y = Yval, group = 1)) + geom_point() + geom_line()  

JW