@Override
public String toOperatorString(CalcFunction function) {
int precedence = getPrecedence();
char operatorChar = '+';
StringBuffer buffer = new StringBuffer();
CalcObject temp;
for (int ii = 0; ii < function.size(); ii++) {
temp = function.get(ii);
if (temp.getHeader().equals(CALC.MULTIPLY)
&& ((CalcFunction) temp).get(0).compareTo(CALC.ZERO) < 0) {
// special case -> negative number
buffer.append(temp);
continue;
} else {
if (ii > 0) {
buffer.append(operatorChar);
}
if (temp.getPrecedence() < precedence) {
buffer.append('(');
}
buffer.append(temp.toString());
if (temp.getPrecedence() < precedence) {
buffer.append(')');
}
}
}
return buffer.toString();
}
@Override
public CalcObject evaluate(CalcFunction input) {
if (input.size() == 1) {
CalcObject parameter = input.get(0);
// parameter = CALC.SYM_EVAL(parameter);
CalcObject returnVal = evaluateObject(parameter);
if (returnVal != null) return returnVal;
else if (parameter instanceof CalcInteger) return evaluateInteger((CalcInteger) parameter);
else if (parameter instanceof CalcDouble) return evaluateDouble((CalcDouble) parameter);
else if (parameter instanceof CalcFraction) return evaluateFraction((CalcFraction) parameter);
else if (parameter instanceof CalcSymbol) return evaluateSymbol((CalcSymbol) parameter);
else if (parameter instanceof CalcFunction) return evaluateFunction((CalcFunction) parameter);
else return input;
} else
return null; // function has more than 1 parameter. This evaluator does not apply so return
// null
}
@Override
protected CalcObject evaluateObject(CalcObject input1, CalcObject input2) {
// optimization cases
if (input1.equals(CALC.ZERO)) {
return input2;
} else if (input2.equals(CALC.ZERO)) {
return input1;
} else if (input1.equals(input2)) {
return CALC.MULTIPLY.createFunction(CALC.TWO, input1);
}
// else if (input1 instanceof CalcSymbol || input2 instanceof CalcSymbol) {
// return CALC.ADD.createFunction(input1, input2); //if either input is a symbol, can't
// evaluate..return original
// }
// end optimization cases
// simplifiable cases
else if (input1.getHeader().equals(CALC.MULTIPLY) && ((CalcFunction) input1).size() > 1) {
CalcFunction function1 = (CalcFunction) input1;
if (function1.get(0).isNumber()) {
if (function1.size() == 2 && function1.get(1).equals(input2)) {
return CALC.MULTIPLY.createFunction(
CALC.ADD.createFunction(CALC.ONE, function1.get(0)), input2);
} else if (input2.getHeader().equals(CALC.MULTIPLY) && ((CalcFunction) input2).size() > 1) {
CalcFunction function2 = (CalcFunction) input2;
if (function2.get(0).isNumber()) {
if (function1.equalsFromIndex(1, function2, 1)) {
CalcFunction result = new CalcFunction(CALC.MULTIPLY, function1, 1, function1.size());
return CALC.MULTIPLY.createFunction(
CALC.ADD.createFunction(function1.get(0), function2.get(0)), result);
}
} else {
if (function1.equalsFromIndex(1, function2, 0)) {
CalcFunction result = new CalcFunction(CALC.MULTIPLY, function1, 1, function1.size());
return CALC.MULTIPLY.createFunction(
CALC.ADD.createFunction(CALC.ONE, function1.get(0)), result);
}
}
}
} else {
if (input2.getHeader().equals(CALC.MULTIPLY) && (((CalcFunction) input2).size() > 1)) {
CalcFunction function2 = (CalcFunction) input2;
if (function2.get(0).isNumber()) {
if (function1.equalsFromIndex(0, function2, 1)) {
CalcFunction result = new CalcFunction(CALC.MULTIPLY, function2, 1, function2.size());
return CALC.MULTIPLY.createFunction(
CALC.ADD.createFunction(CALC.ONE, function2.get(0)), result);
}
}
}
}
}
if (input2.getHeader().equals(CALC.MULTIPLY)
&& (((CalcFunction) input2).size() > 1)
&& ((CalcFunction) input2).get(0).isNumber()) {
CalcFunction function2 = (CalcFunction) input2;
if ((function2.size() == 2) && function2.get(1).equals(input1)) {
return CALC.MULTIPLY.createFunction(
CALC.ADD.createFunction(CALC.ONE, function2.get(0)), input1);
}
}
return null;
}