This model complies with the visitors component interface. It adds
a named list model$visitor.
setup_visitor_trace(model, Wd = NULL, xd = NULL)no return value
an object from make_MicroMoB
a time varying trace of visitor host availability passed to time_patch_varying_parameter
or NULL to set to 0 (no visitors)
a time varying trace of visitor net infectiousness passed to time_patch_varying_parameter
or NULL to set to 0 (no visitors)