Input to the model is provided via a file containing a set of commands and parameter values. The model reads and processes the commands in the order in which they are received. Since the commands are executed sequentially, the model does not include an explicit time step. Rather, the user is required to organize the input commands in the appropriate order.
Comment lines and commands within the input file follow several conventions. To simplify documentation of the command set, comment lines can be inserted at any point by placing a "#" sign in column 1. Within a command line, keywords and parameters are separated by a space. A command may be extended over several lines by placing a "+" sign as the last character on a line. Each command file must begin with several input parameters or commands to initiate the model run. An example is provided below.
1 (run identifier) 5000 (random number seed) 0 (flag for type of run; 0 = stochastic, 1 = deterministic) 2 (number of stocks) SPS NO 500000 50000 GS YES 100000 5000
Line 1 provides a run identifier, line 2 a random number seed, line 3 indicates if the run is stochastic or deterministic, and line 4 indicates the number of stocks in the model run. Subsequent lines in the command file will vary depending upon the application. In this case, lines 5 and 6 provide the initial values for the stocks included in the model run. Fields required are the name of the stock, a flag for identification of mass marked stocks, the total number of fish, and the number of fish which have a CWT. After initialization of the stocks, the user may utilize in any order the commands discussed in Section 3.0.