Plots a sample of ids in a small mutiples layout
plot_sample(dat, layout = c(3, 3), sample = prod(layout), group = NULL)Invisibly returns the number of trajectories plotted.
A data frame with a few id trajectories to plot.
The small multiples layout as c(rows, columns).
If zero, all data in dat are displayed. If >0 a sample of that many data points from dat are displayed.
If not NULL, a character string giving the variable name in data that should color the data points.