The CalculatorGUI project is a powerful and accurate calculator application with a graphical user interface (GUI) built using Java AWT / Swing. It supports basic arithmetic operations along with several additional mathematical functions. The project includes the following classes:

1. CalculatorGUI - The main GUI class for the calculator.
2. Calculator - A utility class that handles expression parsing, conversion to postfix notation, and evaluation.
3. CalculatorTester - A command-line tester for the Calculator class, useful for testing purposes.
4. GraphingTool - A Swing-based graphing tool for plotting mathematical functions.

• Supports basic arithmetic operations: addition (+), subtraction (-), multiplication (*), and division (/).
• Supports exponentiation (^) and parentheses for grouping expressions.
• Additional mathematical functions: square root (sqrt), logarithm (log), trigonometric functions (sin, cos, tan), and factorial (!).
• Dark mode GUI for a modern appearance.
• Input validation via keyboard and button panels and thorough error handling.
• History panel allowing for quick retrieval of past expressions.
• Graphing Tool: Plot mathematical functions graphically using the integrated graphing tool!

• Java Development Kit (JDK) 8 or higher.
• An IDE or text editor for Java development

1. Clone the repository:

   git clone https://github.com/your-username/calculator-gui.git
   cd calculator-gui
   

2. Compile and run the CalculatorGUI class

   javac CalculatorGUI.java
   java CalculatorGUI
   

3. The calculator GUI will launch. You can use either the on-screen buttons or your keyboard to enter expressions. Press Enter or click = to evaluate the expression. Use the "Graph" button to launch the graphing tool and plot your own mathematical functions.