Postfix Evaluation Calculator Online

The Postfix Evaluation Calculator is a powerful tool designed to simplify mathematical expressions in postfix notation. Postfix notation, also known as Reverse Polish Notation (RPN), is a mathematical notation in which every operator follows all of its operands. This calculator allows users to input expressions in postfix notation and calculates the result accurately.

Formula of Postfix Evaluation Calculator

Here’s the formula and explanation of the algorithm:

Function PostfixEvaluation(postfixExpression):
Stack stack
For each token in postfixExpression:
If token is an operand:
Push token onto stack
Else if token is an operator:
operand2 = Pop stack
operand1 = Pop stack
result = PerformOperation(operand1, operand2, token)
Push result onto stack
Return Pop stack

Function PerformOperation(operand1, operand2, operator):
Perform the operation specified by the operator on operand1 and operand2
Return the result

Explanation:

• Initialize an empty stack.
• Scan the postfix expression from left to right.
• For each token:
  • If it’s an operand, push it onto the stack.
  • If it’s an operator, pop the top two operands from the stack, perform the operation specified by the operator on these operands, and push the result back onto the stack.
• After scanning all tokens, the result will be the only value left on the stack, which is the result of the expression.

General Terms Table

Expression	Result
2 3 +	5
4 5 *	20
8 2 /	4
10 3 –	7

Example of Postfix Evaluation Calculator

Let’s consider an example to illustrate how the Postfix Evaluation Calculator works:

Expression: 5 3 8 * 2 / +

Steps:

1. Push 5 onto the stack.
2. Push 3 onto the stack.
3. Push 8 onto the stack.
4. Multiply the top two operands (8 * 3 = 24) and push the result onto the stack.
5. Push 2 onto the stack.
6. Divide the top two operands (24 / 2 = 12) and push the result onto the stack.
7. Add the top two operands (12 + 5 = 17), which is the final result.

Result: 17

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