Generate the stoichiometry (|u| by |v|) matrix for the SPN. Each column gives the net effect of that transition firing upon the state space of the model. Internally, this creates a Pre (spn_Pre) and Post (spn_Post) matrix, and then calculates the final stoichiometry.

spn_S(spn_P, spn_T)

## Arguments

spn_P set of places (P) (see details) set of transitions (T) (see details)

## Details

The places (spn_P) object is generated from one of the following: spn_P_lifecycle_node, spn_P_lifecycle_network, spn_P_epiSIS_node, spn_P_epiSIS_network, spn_P_epiSEIR_node, or spn_P_epiSEIR_network.

The set of transitions (spn_T) is generated from one of the following: spn_T_lifecycle_node, spn_T_lifecycle_network, spn_T_epiSIS_node, spn_T_epiSIS_network, spn_T_epiSEIR_node, spn_T_epiSEIR_network.