An Extensible Arithmetic Evaluator written in java

Character Set

[0-9], [a-z], {+, -, /, *}, {., (, )}

operations supported :
Addition
Subtraction
Multiplication
Division
Sine
Cosine
Tangent
Logarithm
Identity

Usage

    sample expression : 
    
    
    Case 1 : input syntax is correct
    log(log(log(tan(105/100)*12.4+1)))
    Output :
    parse success
    true
    -0.8802202256366045
    
    Case 2 : wrong input syntax
    log(log(log(tan(105/100)*12.4+1))
    Output :
    Exception in thread "main" closing parenthesis required !
    	at com.artevaluator.grammar.Parser.factor(Parser.java:180)
    	at com.artevaluator.grammar.Parser.term(Parser.java:92)
    	at com.artevaluator.grammar.Parser.expr(Parser.java:27)
    	at com.artevaluator.grammar.Parser.isValid(Parser.java:203)
    	at com.artevaluator.Main.main(Main.java:30)

How can It be extended

• Determine the new operator
• If operator uses any new character add that character to the character-set in Literals.java
• Design a DFA which could recognize the new operator with distinct Accept State.
• Add the code for the dfa to Lexer.java
• Add another implementation for the operator interface in operators package and override the solved method based on unary or binary operator
• add the new operator object to the ops HashMap in Node.java at the end of file.