Running the code

Author: Andreas Slovacek Date: 23 September 2018

System Requirements

• Unix based OS
• Python 3.x
• Tested on OSX 10.13.4; Kali Gnu/Linux Rolling

Knowing the the files

Please see ./html/index.html for Doxygen generation. It is complete documentation.

Functions are listed in the order they are called.

fa_master.py

Master script. Reads directories and passes definition files to FA constructor and string processor

• run(self) calls sub-functions
  • build_fas(self) calls sub-function to scan directory for .fa files, then passes those to the FA constructor
  • get_input_strings(self,input_file) creates an iterable list of all strings from input.txt
  • Run then calls on each FA to process_string()

finite_automaton.py

Implementation of NFA. DFA functionality handled the same as the NFA, except strings containing epsilon transitions aren't processed.

• process_def(self,from_file) set's up a Finite Automaton based on a .fa files definition.

  • fa_type() determines the type of the FA by checking duplicate transitions, epsilon tranisitons, invalid accepts states, accept state range, state range
  • set_alphabet() extracts the alphabet from the transition table
  • set_states() extracts the states from the transition table
  • get_dupe_set() extracts duplicate transitions from the transition table

• process_string(in_string) used to test strings in the FA. The current states is reset with every string processed. IF-ELIF-ELSE finds reasons to cease processing. Otherwise process the string, check if it ended in an accept state, and save the string if it did.

  • self.strings_processed tracks how many strings this FA has processed
  • next_state_recurse(in_str) recursively processes the string and shifts states

• finalize_fa() Logs the FA values in results/basename.log and echos the accepted strings into results/basename.txt. Called from fa_master.py

• print_self() Call after process_def to print the FA to CLI

fa_logger.py

Handles file and directory operations.

• log_FA(FA) Takes an FA as parameter, sets up and writes log files
  • set_filenames(filename) creates a directory for results if needed and sets directory/filenames for the .log and .txt file associated with this FA
  • remove_previous_files() deletes any existing .log and .txt files
  • create_log_file(FA) writes (Valid,States,Alphabet,Accepted Strings) to .log file with input parameter FA's member variables
  • create_txt_file(FA) writes accepted strings to .txt with input parameter FA's member variables

cleanup.sh

Cleans residual .log and .txt files in PJ01/results

code/

Contains the Python files

results/

Contains the output .log and .txt files generated in fa_logger.py

NFA_DFA_Maker

Finite Automaton creator and classifier based on PJ01.pdf

In this project you will write a program that will read a simplified description of a finite automaton, validate it, and then simulate it on each string read from an input text file. Each string that is accepted by the DFA will be echoed to a text file; in addition each machine will have a log file prepared containing specific pieces of information.

To avoid operating-specific case-sensitivity issues, all filenames will be all lowercase. So that all of the files can be in the same directory and the following naming conventions will be used:

• Base name: mxx where xx is a two digit number. The first machine will have a base name of m00 and the remaining machines will be numbered sequentially. This should allow you to write a wrapper program that processes all of the machines in a single run.
• Machine description file: basename.fa
• Accepted strings: basename.txt
• Log file: basename.log
• Input file: strings.txt (the same file for all machines)