convert individual event information to aggregated information per network node
aggr_data(dat, from = NULL, cumsum = TRUE)
logical indicating whether data is aggregated by cumulative sum, default is
data.frame of dimension
T is the number of observation times and
K the number of network nodes. Thus, each row represents a snapshot of the spreading process at a specific observation time with the event magnitude observed at the network nodes. Rownames are observation times, colnames are node names.