Evaluating postfix expressions in java
<p>I have a problem i can't find the wrong in this function it sometimes do well with some inputs but sometimes no for examle this Input "6 2 / 3 – 4  2 * +" can any one help.</p>

<pre><code>public static double Evaluating_postfix_expressions(String postfix) throws Exception{
    StringTokenizer st = new StringTokenizer(postfix);
    int numOF_tokens = st.countTokens();
    for (int i = 1; i &lt;= numOF_tokens; i++) {
        Object term = st.nextToken();
        try { // if it is an operand there is no problem
            float x =  Float.parseFloat((String)term);
            stack.push(x);
        } catch (Exception e) { // it is an operator
            float v1 = (float) stack.pop();
            float v2 = (float) stack.pop();
            switch ((String) term) {
            case "+":
                stack.push(v2 + v1);
                break;
            case "-":
                stack.push(v2 - v1);
                break;
            case "*":
                stack.push(v2 * v1);
                break;
            case "/":
                stack.push(v2 / v1);
                break;
            }
        }
    }
    return (float) stack.pop();
}
</code></pre>
