/**
* Converts a string containing a mathematical expression in infix form to postfix form. The
* result is stored in the vector m_postfixExpVector
*
* @param infixExp the infix expression to convert
* @exception Exception if something goes wrong during the conversion
*/
private void convertInfixToPostfix(String infixExp) throws Exception {
infixExp = Utils.removeSubstring(infixExp, " ");
infixExp = Utils.replaceSubstring(infixExp, "log", "l");
infixExp = Utils.replaceSubstring(infixExp, "abs", "b");
infixExp = Utils.replaceSubstring(infixExp, "cos", "c");
infixExp = Utils.replaceSubstring(infixExp, "exp", "e");
infixExp = Utils.replaceSubstring(infixExp, "sqrt", "s");
infixExp = Utils.replaceSubstring(infixExp, "floor", "f");
infixExp = Utils.replaceSubstring(infixExp, "ceil", "h");
infixExp = Utils.replaceSubstring(infixExp, "rint", "r");
infixExp = Utils.replaceSubstring(infixExp, "tan", "t");
infixExp = Utils.replaceSubstring(infixExp, "sin", "n");
StringTokenizer tokenizer = new StringTokenizer(infixExp, OPERATORS, true);
m_postFixExpVector = new Vector();
while (tokenizer.hasMoreTokens()) {
String tok = tokenizer.nextToken();
if (tok.length() > 1) {
handleOperand(tok);
} else {
// probably an operator, but could be a single char operand
if (isOperator(tok.charAt(0))) {
handleOperator(tok);
} else {
// should be a numeric constant
handleOperand(tok);
}
}
m_previousTok = tok;
}
while (!m_operatorStack.empty()) {
String popop = (String) (m_operatorStack.pop());
if (popop.charAt(0) == '(' || popop.charAt(0) == ')') {
throw new Exception("Mis-matched parenthesis!");
}
m_postFixExpVector.addElement(new Operator(popop.charAt(0)));
}
}
