Passing data argument inside geom_segment doesn't work

[Kevin Middleton]

Passing data inside of geom_segment leads to a warning:

Ignoring unknown aesthetics: z, zend

and no plot. Using the demo code:

df <- data.frame(x=0.6,y=0.2,z=0.2,xend=0.2,yend=0.6,zend=0.2)

ggtern(data=df,aes(x,y,z,xend=xend,yend=yend,zend=zend)) +
  geom_segment(size=2,arrow=arrow(),color="red")

works as expected, but

ggtern() +
  geom_segment(data=df,aes(x,y,z,xend=xend,yend=yend,zend=zend),
               size=2,arrow=arrow(),color="red")

does not with the warning above.

[Benjamin LeRoy]

I’ve seen this relative to ggplot functions. I think it may be how ggtern updates to z values. This also occurs with other functions like geom_line, when the aes call is in geom_line.

‌

This is related to the code in: https://bitbucket.org/nicholasehamilton/ggtern/src/master/R/ggtern-constructor.R

[Kevin Middleton]

I’ve had the same problem in ggplot, which you can get around by creating an empty ggplot() and then adding geoms with data =. Until very recently this also worked with ggtern (I have code that ran fine until the most recent updates).