Interactive Experiments

Values assigned to variables in the INIT section can be changed interactively during the simulation or between different runs of the same model. To do that, the assignation instructions must be included between the words EXPER and ENDEXP. The variables in this range are called experimental variables. The assignation must be of the form:

<identifier> := <value(s)>

<identifier> corresponds to a experimental variable of the type:

• simple variable.
• element of an array.
• name of a type R node.
• functions given by pairs of values.
• name of a frequency table.

When the option read Experiment and continue is selected in the Menu, the system displays the values of these variables in the form:

<identifier> = <value(s)>

and it askes for a file name. This file will contain the assignation of the experimental variables in the defined format. The order and quantity may be different of those of the declaration in the INIT.

Example:

 EXPER
 TSIM := 6000;  A := 5.08;
 Fx := 1. 3, 8 / 5, 2 / 8, 1;
 Reci := 6.0;
 S := 7;
 Table2 := 0, 12, 2, 5;
 ENDEXP

The program will be run with the assigned values of these variables. If the E option in the run interactive menu (see section 10.5) is selected, the system prompts:

ENTER NAME OF DATA FILE

The user must write the name of an input data file (may be CON for the keyboard). The file must begin for a line with a title for the experiment and lines follows of assignation like those in the INIT without the characters / ; or : For instance:

 Fx = 1.3 8   5 2
      8 1
 S := 7   Table2 = 0 12 2
 TSIM = 6000
 END

The system reads the data and assigns the values to the variables until the END is found. The system display the new values that can be corrected or accepted by the user. When accepted, the simulation continues.