First, some context. Are we correct in assuming you are referring to this example?
There are several helper function used in this example. You can access these by opening the example in your local install of MATLAB. In the top right of the page, click Copy Command then run the copied command in your Command Window. This will download the example files and change your Current Folder to the example folder.
The command is openExample('scenariobuilder/EgoVehicleLocalizationUsingGPSAndIMUFusionExample')
