In the case of least-squares fit of experimental data, the process of "trying" a script file consists of simulating the model behavior, using the initial estimate of fitting parameters (rate constants and concentrations), and displaying the comparison between the data and the model in the graphical output window. This feature is especially useful in deciding on the initial estimates for the adjustable model parameters.

To try the script loaded in this example problem, select 'Try' from the 'File' menu.

The program will process the loaded script and simulate the theoretical curve corresponding to the parameters in the script. In the figure below we see that the theoretical curve (smooth green curve) and the experimental data (yellow boxes) are not in a perfect agreement, because the script contains only initial estimates of rate constants.