Identify points in plot

Identify points in a plot, similarly to the identify function in base graphics.

identify3d(x, y = NULL, z = NULL, labels = seq_along(x), n = length(x), 
  plot = TRUE, adj = c(-0.1, 0.5), tolerance = 20, 
  buttons = c("right", "middle"))

Arguments

x, y, z

coordinates of points in a scatter plot. Alternatively, any object which defines coordinates (see xyz.coords) can be given as x, and y and z left missing.

labels

an optional character vector giving labels for the points. Will be coerced using as.character, and recycled if necessary to the length of x.

n

the maximum number of points to be identified.

plot

logical: if plot is TRUE, the labels are printed near the points and if FALSE they are omitted.

adj

numeric vector to use as adj parameter to text3d when plotting the labels.

tolerance

the maximal distance (in pixels) for the pointer to be ‘close enough’ to a point.

buttons

a length 1 or 2 character vector giving the buttons to use for selection and quitting.

Details

If buttons is length 1, the user can quit by reaching n selections, or by hitting the escape key, but the result will be lost if escape is used.

Value

A vector of selected indices.

Author

Duncan Murdoch

See also

identify for base graphics, select3d for selecting regions.