# The Sketchable Graph

A Sketchable graph enables users of your model to create a sketch of the expected behavior for some model variable, over the course of a simulation run. When the simulation is run, the user will be able to compare their expected behavior against the actual behavior of the variable. Sketchable graphs come in handy when you want users of your model to "put a stake in the ground" regarding the performance of the model. Discrepancies between expected and actual performance can motivate effective, efficient learning experiences.

To create a sketchable graph, open a graph pad's Define dialog, and then select the Sketchable graph type option. When you do, the dialog will look something like what's shown in Figure 6-56.

Figure 6-56 Sketchable Graph Dialog

Note that you can load only one variable to a sketchable graph. The graph will display output for the variable, along with a user-provided sketch for the variable. The variable and its sketch will share a common scale. You must provide a scale. The process outlined in Scaling Variables shows you how to scale variables..

Whenever you create a sketchable graph, the Benchmark check box is automatically checked for you. Benchmark enables the user of your model to re-draw an entire Sketch during pauses mid-simulation, or even while the simulation is running. When Benchmark is not checked, the user can only redraw that portion of the graph that is beyond the current simulation time. No "History" (the part of the simulation that has already run) can be "re-written."

To create a sketch, click within the axes and drag in the desired pattern over time. Figure 6-57, below, shows the resultant sketchable graph after a simulation run has been completed. Note that both the actual model variable, and the sketch of expected behavior, appear on the graph.

Helpful Hint: When you use sketchable graphs, it's always a good idea to provide the user of your model with some instructions. Use an info button, a text box, a sound, or even the annotation cache that's part of the graph pad page to provide the user with a brief set of instructions.

Figure 6-57 Sketchable Graph Output