The points in the d marginal processes \(N_{1}\), \(N_{2}\) ,..., \(N_{d}\) of a vector
of point processes are plotted versus the time index.
If one of the arguments date
and axispoints
is NULL, default axis are used.
Otherwise, the values in axispoints
are used as the points in the time index in which axis ticks
and labels, from date
, are drawn.