getXY(n = -1, ..., unit = "native", scale.correction = NULL)
getLatLon(..., map = NULL, object = trellis.last.object(),
scale.correction = function(x) {
temp <- XY2LatLon(map, x$x, x$y)
as.list(as.data.frame(temp))
})
screenLatticePlot(object = trellis.last.object(), ...)"native".getLatLon only. The plot layer as
generated makeMapArg and the plot object genereated by
GoogleMap. The map is strictly required as a reference when
converting plot points to associatetrellis.focus for panel selection (if working with multi-panel
plots) and getXY returns the x and y coordinates of
the selected points on a plot as a list containing two
components, x and y.
getLatLon returns the latitude and longitude
values of the selected points on a map as a list
containing two components, lat and lon.getXY is an interactive function which returns
the locations of points on a plot selected using the
mouse (left click to select points; right click and
stop to end point collection; escape to abort without
returning any values).
It is a wrapper for the grid function
grid.locator that behaves more like
locator, the equivalent function intended
for use with plot outputs.
By default getXY selections are not automatically
marked. Adding common plot parameters to the function
call overrides this behaviour, e.g. to add red symbols
and lines.
ans <- getXY(col = "red", pch = 4, type = "b")
getXY also provides a mechanism to handle data plotted on
locally scaled axes. See Note below.
getLatLon is wrapper for getXY for use
with GoogleMap outputs and other similarly
georeferenced plots. See Note below.
screenLatticePlot is a crude plot screening function. It is
currently in development.grid.locator;
trellis.focus and lpoints in lattice.
See LatLon2XY in RgoogleMap.