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(NFA) InvalidStateError: end state q for transition on q0 is not valid

See original GitHub issue

hey i ve getting this error while using “nfa.accepts_input(my_input_str)” in my project , i tried the same structure of the automata in a seperate file and it functionned properly , im wondering if anyone could guide me a little to figure out what to fix ( or at least the scenarios that may lead to this error thanks! here’s my project link

automata.base.exceptions.InvalidStateError: end state q for transition on q0 is not valid

Issue Analytics

  • State:closed
  • Created a year ago
  • Comments:5 (3 by maintainers)

github_iconTop GitHub Comments

caleb531commented, Aug 17, 2022

@maryembenali Perfect, I was able to reproduce the error. I’m pasting it here so I can reference it later:

Exception in Tkinter callback
Traceback (most recent call last):
  File "/opt/homebrew/Cellar/python@3.9/3.9.13_1/Frameworks/Python.framework/Versions/3.9/lib/python3.9/tkinter/", line 1892, in __call__
    return self.func(*args)
  File "/Users/caleb/Desktop/automata-trial2/", line 127, in Verify_Word
    nfa = NFA(states=set(States),input_symbols=set(Letters_List),transitions=Transitions_Dict,initial_state=Initial_state[0],final_states=set(final_states))
  File "/Users/caleb/Desktop/automata-trial2/.virtualenv/lib/python3.9/site-packages/automata/fa/", line 21, in __init__
  File "/Users/caleb/Desktop/automata-trial2/.virtualenv/lib/python3.9/site-packages/automata/fa/", line 70, in validate
    self._validate_transition_end_states(start_state, paths)
  File "/Users/caleb/Desktop/automata-trial2/.virtualenv/lib/python3.9/site-packages/automata/fa/", line 62, in _validate_transition_end_states
    raise exceptions.InvalidStateError(
automata.base.exceptions.InvalidStateError: end state q for transition on q0 is not valid

I will start debugging later today or tomorrow. I need to take a break right now.

maryembenalicommented, Aug 17, 2022

These are the inputs i tried to enter

  • tick non-deterministic (doesn’t do anything for the moment)
  • 2
  • a b
  • 3
  • {“q0”: {“a”: “q1”}, “q1”: {“a”: “q1”, “b”: “q2”},“q2”: {“b”: “q0”}}
  • q0
  • 1
  • q1 Also i recommend to change the path of the image so it can be displayed properly Thank u very much!
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