Calculates the probability that a queueing system has exactly State customers in it--either being served or waiting. (This function is the probability distribution on the number of customers in the system).
QTPMMS_PrState(State, Arrival Rate, Service Rate, Servers)
There is an option to use a finite Queue Capacity, where customers in excess of Queue Capacity are not admitted to the queue:
QTPMMS_PrState(State, Arrival Rate, Service Rate, Servers, Queue Capacity)
If the Queue Capacity argument is omitted, it is assumed infinite.