Plots an x-y, time-x, time-y track of a potential migration process and prompts the user to click on the figure to obtain initial estimates of range centroids and timing of start and end of migrations.
locate_shift(time, x, y, n.clust =2,...)
Arguments
time: time (can be a POSIXt)
x: x and y coordinates. Can be two separate vectors OR a complex "x" OR a two-column matrix/date-frame.
y: see x
n.clust: number of ranges (either 2 or 3)
...: additional parameters to pass to plot functions
Returns
a named vector of initial estimates: if n.clust = 2, c(x1, x2, y1, y2, t1, dt) if n.clust = 3, c(x1, x2, x3, y1, y2, y3, t1, t2, dt1, dt2)