Uses the exported C++ helpers get_riskset and
convert_to_risksetMatrix with 0-based actor IDs, matching the
convention used internally by tomstats.
.build_riskset_matrix(N, directed, C = 1L)Numeric matrix of dyad IDs (0-based, -999 for absent dyads). Dimensions N × N when C = 1; N*C × N*C when C > 1.
Number of actors.
Logical.
Number of event types (default 1).