Expert_system

General-purpose Expert system for various conclusions

Present Expert system is based on backward chaining algorithm

Run

> ./expert.py your_knowledge_base_file

OR

> python3 expert.py your_knowledge_base_file

Format of file

• At first, your file should have rules separated by new line
• Every rule should have conlusion by => - implication operator or <=> - logical equality operator. For example: A => B # A implies B
• Comment starting by # symbol
• In the end of file you can initialize facts to true (by default all facts = false) after = operator. For example: = fact1, fact2, fact3, fact4... or simple form =ABCDEF... (if facts named only by one letter) -> fact A = true, fact B = true, fact C = true...
• After that you can ask a condition of the fact (true or false) by ? operator. For example ? fact1, fact2, fact3... or in simple form ?ABD -> fact A - ?, fact B - ?...

Logical operators

• + - logical operator AND
• | - logical operator OR
• ^ - logical operator XOR
• ! - logical operator NOT
• ( and ) - standart mathematical brackets

File example

File examples/AND_OR1.ex

S | E | V => V
V + !V => C

=S # initialize S to true
?VC # Results V - true, C - false

File examples/XOR1.ex

A ^ (X | Y) => V
N + (B ^ V) ^ !V => S

=XBN # initialize X, B and N to true
?SV # Results: S - false, V - true

Other

After file is read and results is displayed, you can in console mode add rules and facts, initialize facts (by operator =) and display results (by operator ?)

Besides that, in console mode you can:

• Reset all rules by next command

>> remove base

• Reset all facts initialized to true

>> remove facts

• Read other file (reading base and display results)

>> open path/to/file