The PiFace CAD emulator allows you to use CAD methods in your projects when you haven't got a PiFace CAD board handy.
To install the emulator, open a Terminal and update your Raspberry Pi's package lists using the command
sudo apt-get update
Now install the PiFace CAD emulator package by typing
sudo apt-get install python3-pifacecad-emulator
Enter y when instructed.
Now that the emulator is installed, to use it you must be in the graphical environment, if you are not, enter the command
To start the emulator you can either click the desktop icon PiFace CAD Emulator or open a Terminal and enter
You will see the emulator appear on your screen
You can also use the emulator in a python shell or program
import pifacecad_emulator as p
cad = p.PiFaceCAD()
Then you can use the cad object as you would do normally.