It's all very well designing a Turing machine using a computer program, but typically we want to do a little more than this. We usually would like to know how our machine behaves when given certain inputs.
Given that Tuatara Turing Machine Simulator is designed for teaching purposes, frequently we also like to see exactly how our machine arrives at its output - what steps were involved, and why those steps took place. Hence, simulating the execution of Turing machines step-by-step is part of the core functionality of this program.
This guide explains in detail how to control the simulation of your shiny new Turing machines.
To make the current machine step through one single operation, choose the
Stepe item from
the Machine menu or the toolbar. The machine will complete the operation specified by one transition.
The tape and the state of the machine will be updated accordingly.
Select Execute from the Machine menu or toolbar to
start the simulation running. The machine's
execution will occur continuously and automatically until the computation halts (in error or otherwise)
or the user presses the stop or pause buttons. The
Stop Execution and
Pause Execution buttons
are also located in the Machine menu and toolbar.
The speed of execution can be controlled via the options in the Machine menu. This is useful for debugging or learning purposes, or to reduce the waiting time for a computation to complete. The speed cannot be modified during automatic execution.
The current state of the machine can be modified using the
Choose Current State mode, found in the Mode menu and toolbar. This is useful for debugging and
exploring 'what-if' scenarios. When in this mode, click on a state to select it as the current state.
This program can somewhat handle non-deterministic machines. When the machine is in a state which has more than one outgoing transition for which the input symbol matches the symbol on the tape, a valid transition is chosen randomly. The randomly selected next transition is shown in pink in the display window.
When the machine is paused, you may determine which transition will be executed using the
Choose Next Transition mode from the Mode menu/toolbar.
When in this mode, click on a legal transition to select it as the next transition.