Mathagician

Math Operation Evaluator and Calculator base on Shunting-yard algorithm.

Default

• Number type:
  • Integer
  • Double
• Operator:
  • Basic: +, -, *, /
  • Advance: %, ^, !
  • Comparison: =, <, <=, >, >=, !=
• Notation:
  • Custom Parenthesis (Default: ())
  • Custom Argument Separator (Default: ,)
• Constant:
  • pi or π
  • e
  • φ
• Function:
  • Trigonometry: sin, cos, tan, csc, sec, cot
• Builder:
  • OperationBuilder: Building an Operation object to evaluate.
  • ComparisonBuilder: Building a Comparison object to compare two operations.

Operation Examples

• Usage (Calculation)

OperationBuilder operation = new OperationBuilder("sin(30)/cos(30)")
    .parse();
double result = operation.build().eval();
// result = 0.5773502691896256;

• Usage (Reverse Polish Converter)

OperationBuilder operation = new OperationBuilder("sin(30)/cos(30)")
    .parse();
String reversePolish = operation.build().toString();
// reversePolish = "30.0 sin 30.0 cos /";

• Custom operator

Parameters: Key, Name, Arity (UNARY or BINARY), Precedence (ADDITION, MULTIPLICATION, POWER, or FORCE), isLeftAssociative

Operator op = new Operator("√", "sqrt", Operator.ARITY_BINARY, Operator.POWER, false){
    @Override
    public Operand operate(Operand... operands) {
        if(operands[0].getNumber() < 0)
            throw new ArithmeticException("Imaginary number.");

        return new Operand(Math.sqrt(operand[0].getNumber())));
    }
});

OperationBuilder operation = new OperationBuilder("√4")
    .addOperator(op).parse();
double result = operation.build().eval();

• Custom constant

Constant cs = new Constant(6.022 * Math.pow(10, 23), "mol", "mole", "L");
OperationBuilder operation = new OperationBuilder("12mol")
    .addConstant(cs).parse();
double result = operation.build().eval();

• Custom notation

OperationBuilder operation = new OperationBuilder("[2^3]+1")
    .setParenthesis("[", "]").parse();
double result = operation.build().eval();

• Custom function
  

Function ft = new Function("round", 1) {
    @Override
    public Operand function(Operand... operands) {
        return new Operand(Math.round(operand[0].getNumber()));
    }
});
OperationBuilder operation = new OperationBuilder("round(3.14)")
    .addFunction(ft).parse();
double result = operation.build().eval();

Note: operation.OperationBuilder#add(Operator|Constant|Function) can accept varargs

Comparison Examples

• Usage (String Constructor)

ComparisonBuilder operation = new ComparisonBuilder("sin(30)/cos(30) > 1")
    .parse();
boolean result = operation.build().eval();
// result = false;

• Usage (Operations Constructor)

Operation op1 = new OperationBuilder("sin(30)/cos(30)").parse().build();
Operation op2 = new OperationBuilder("1").parse().build();

ComparisonBuilder operation = new ComparisonBuilder(op1, ">", op2); 
// Do not use ComparisonBuilder#parse when there are already defined operations.

boolean result = operation.build().eval();
// result = false;

Todo List

• More operators...
• More Functions...
• Comparison Evaluator
• Better Error Handling (Identifying Errors)
• Variables: operation.OperationBuilder#setVariable("x", "1")