Running Python Programs

Python is a popular and versatile programming language used for various applications. Once you have written your Python code, you need to run it to see the results. In this tutorial, we will cover the different ways to run a Python program.

Introduction to Running Python Programs

To run a Python program, you need to have Python installed on your computer and a text editor or an Integrated Development Environment (IDE) like Komodo Edit, IDLE, or PyCharm. You can write your Python code in any text editor, but using an IDE provides additional features like syntax highlighting, debugging, and execution.

Running Python from the Command Line

The most common way to run a Python program is from the command line. Here are the steps:

1. Save your Python file: Save your Python code in a file with a .py extension, for example, hello.py.
2. Open a terminal or command prompt: On Windows, you can press Win + R and type cmd to open the Command Prompt. On macOS or Linux, you can use Terminal.
3. Navigate to the directory: Use the cd command to navigate to the directory where your Python file is saved. For example, if your file is on the desktop, you can use cd Desktop.
4. Run the Python program: Type python filename.py and press Enter to run the program.

If you get an error message saying that python is not recognized as a command, it means that Python is not in your system’s PATH. You need to add the Python executable to your system’s PATH environment variable.

Adding Python to Your System’s PATH

To add Python to your system’s PATH on Windows:

1. Right-click on Computer or This PC and select Properties.
2. Click on Advanced system settings on the left side.
3. Click on Environment Variables.
4. Under System Variables, scroll down and find the Path variable, then click Edit.
5. Click New and enter the path to the Python executable (usually C:\PythonXX\bin, where XX is the version number).
6. Click OK to close all the windows.

After adding Python to your system’s PATH, you can run your Python program from any directory using the command python filename.py.

Running Python from an IDE

Most IDEs provide a way to run Python programs directly from within the editor. Here are some examples:

• In IDLE, you can press F5 or select Run > Run Module to run the current file.
• In Komodo Edit, you can create a new command in the Toolbox to run Python files. To do this:
  1. Go to Toolbox > Add > New Command…
  2. Enter a name for the command, such as "Run Python file".
  3. In the Command field, enter %(python) %F.
  4. Click OK.

Example Code

Let’s create a simple Python program to print "Hello, World!" to the console:

print("Hello, World!")

Save this code in a file called hello.py and run it using one of the methods described above.

In conclusion, running a Python program is a straightforward process that can be done from the command line or from within an IDE. By following these steps and examples, you should be able to run your own Python programs with ease.