Locator for ggplot objects
Locator for ggplot objects (Note : only accurate when extent = "normal" when using ggmap.)
gglocator(n = 1, message = FALSE, mercator = TRUE, ...)
n |
number of points to locate. |
message |
unused |
mercator |
logical flag; should the plot be treated as using the projection common to most web map services? Set to FALSE if the axes on the plot use a linear scale. |
... |
additional arguments (including deprecated, e.g. xexpand) |
a data frame with columns according to the x and y aesthetics
Tyler Rinker, Baptiste Auguie, DWin, David Kahle, \@Nikolai-Hlubek and \@mvkorpel.
if (interactive()) {
# only run for interactive sessions
df <- expand.grid(x = 0:-5, y = 0:-5)
ggplot(df, aes(x, y)) + geom_point() +
annotate(geom = "point", x = -2, y = -2, colour = "red")
(pt <- gglocator(mercator = FALSE)) # click red point
last_plot() +
annotate("point", pt$x, pt$y, color = "blue", size = 3, alpha = .5)
hdf <- get_map("houston, texas")
ggmap(hdf, extent = "normal")
(pt <- gglocator(mercator = TRUE))
last_plot() +
annotate("point", pt$lon, pt$lat, color = "blue", size = 3, alpha = .5)
}Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.