Calculator WPF

Cross-platform decimal calculator with WPF (Windows) and Avalonia (macOS/Linux) interfaces. Supports basic math operations, decimals, and batch file processing.

📥 Installation

macOS Users

⚠️ Important: If you get a "damaged app" error when opening the DMG, see INSTALL_MACOS.md for simple fix instructions.

Quick fix in Terminal:

xattr -cr ~/Downloads/CalculatorWPF.app

Windows Users

Download the appropriate ZIP file for your system:

• Windows x64: Most modern Windows PCs
• Windows ARM64: ARM-based Windows devices (Surface Pro X, etc.)

Extract and run CalculatorWPF.exe

Features

• Basic operations: +, -, *, /
• Decimal number support: 3.14, 0.5, .25
• Power/exponentiation: ^
• Parentheses for grouping: ( )
• Proper operator precedence using RPN (Reverse Polish Notation)
  • Parentheses (highest)
  • Exponentiation (^) - right associative
  • Multiplication and Division
  • Addition and Subtraction (lowest)
• Negative numbers and negative exponents
• Decimal precision (28-29 digits)
• Batch file processing
• Async file operations

Requirements

• .NET 10 SDK
• Windows (WPF requires Windows)

Building

dotnet build

Running

dotnet run --project CalculatorWPF/CalculatorWPF.csproj

Or open in Visual Studio and press F5.

Testing

dotnet test

Usage

Calculator Tab

Enter an expression and click Calculate or press Enter.

Examples:

• 2 + 3 * 2 = 8
• (2 + 3) * 2 = 10
• 2 ^ 3 = 8
• 2 ^ 3 ^ 2 = 512 (right associative: 2^(3^2))
• (2 + 3) ^ 2 = 25
• 10 - 5 = 5
• -3 * 4 = -12
• ((2 + 3) * 4) ^ 2 - 10 = 390

Batch Processing Tab

1. Select input file (one expression per line)
2. Choose output file path
3. Click Process File

Input file example:

2 + 3 * 2
(2 + 3) * 2
2 ^ 3
10 - 5
-3 * 4

Output file:

8
10
8
5
-12

Error Messages

• Division by zero: Error - Division by zero
• Invalid characters: Error - Invalid character: 'x'
• Decimals not supported: Error - Decimal numbers are not supported
• Empty expression: Error - Expression cannot be empty
• Mismatched parentheses: Error - Mismatched parentheses: unclosed opening parenthesis
• Negative exponents: Error - Negative exponents are not supported

Project Structure

CalculatorWPF/
├── CalculatorWPF/
│   ├── Models/
│   │   └── Token.cs
│   ├── Services/
│   │   ├── Tokenizer.cs
│   │   ├── RpnConverter.cs
│   │   ├── ExpressionEvaluator.cs
│   │   ├── CalculatorEngine.cs
│   │   └── FileProcessor.cs
│   └── MainWindow.xaml
└── CalculatorWPF.Tests/
    └── Services/
        ├── TokenizerTests.cs
        ├── RpnConverterTests.cs
        ├── ExpressionEvaluatorTests.cs
        ├── ParenthesesTests.cs
        ├── ParenthesesValidationTests.cs
        ├── PowerOperatorTests.cs
        ├── ComplexExpressionTests.cs
        └── (other test files)

Implementation Details

The calculator uses Reverse Polish Notation (RPN) with the Shunting Yard algorithm for proper order of operations:

1. Tokenizer: Converts input string into tokens (numbers, operators, parentheses)
2. RpnConverter: Converts infix notation to RPN using Shunting Yard algorithm
3. ExpressionEvaluator: Evaluates RPN expression using a stack-based approach

This approach ensures:

• Correct operator precedence
• Proper handling of parentheses
• Right-associativity for exponentiation
• Efficient evaluation