Building a basic calculator with Python and PyQt
Write a Python program that builds a basic calculator application with buttons for numbers and operators using PyQt. When buttons are clicked, they display the input and perform calculations.
From doc.qt.io:
QApplication Class: The QApplication class manages the GUI application's control flow and main settings.
QMainWindow Class: The QMainWindow class provides a main application window.
QPushButton: The push button, or command button, is perhaps the most commonly used widget in any graphical user interface. Push (click) a button to command the computer to perform some action, or to answer a question. Typical buttons are OK, Apply, Cancel, Close, Yes, No and Help.
QVBoxLayout Class: The QVBoxLayout class lines up widgets vertically.
QHBoxLayout Class: The QHBoxLayout class lines up widgets horizontally.
QWidget: The QWidget class is the base class of all user interface objects.
QLineEdit Class: The QLineEdit widget is a one-line text editor.
Qt module: PyQt5 is a set of Python bindings for the Qt application framework. It allows us to use Qt, a popular C++ framework, to create graphical user interfaces (GUIs) in Python.
Sample Solution:
Python Code:
Explanation:
The above code creates a basic calculator with buttons for numbers (0-9) and operators (+, -, *, /). Users can input an expression by clicking on the buttons. Clicking the "=" button will calculate the result, which will be displayed in the input field.
Output:
Flowchart:



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