Maybe you think that grid
is no more supported because of the message displayed on its CRAN page ? But if it is written that Package ‘grid’ was removed from the CRAN repository, it is because it is now part of the base R distribution, as mentioned on Paul Murrell's grid
page.
So library(grid)
and the arrow
function should work fine.
Some of the confusion may be due to the fact that grid
was loaded automatically by previous versions of ggplot
(making grid
functions visible/accessible to the user); now it's referred to via NAMESPACE imports instead, so you need to explicitly load grid
if you want to use grid
functions (or look at their help pages).
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