Want to learn Python? Check out all the Python tutorials on PythonGuides.com. All these tutorials are written by Python experts with practical and real examples. Talk with our experts if you still have questions.
Imagine you just joined a new team and your manager says, “We need a prototype this week, but the final product must be fast and rock solid.” One teammate suggests Python because it’s quick to write. Another pushes for C++ because it’s faster at runtime and great for performance-critical systems. You know both names, but you are not sure … Read more >>
You’re looping through a list of monthly sales, and suddenly your script crashes with IndexError: list index out of range. You were sure that index 5 existed, but your data source had fewer months than you expected. Now your report is broken, and you’re not sure why. This is a very common problem when you … Read more >>
As a developer, I often work with Word documents, Excel workbooks, PowerPoint presentations, and ZIP files that contain important or confidential information. Protecting each file manually can become repetitive, especially when working with different file types. To make this process easier, I decided to Build a File Password Protector in Python. With a single desktop … Read more >>
You pull your monthly sales report, run a quick average, and the result looks weird. You scroll through the data and see those annoying NaN values mixed in with real numbers. Your chart is broken, and your summary numbers no longer make sense. NaN means “Not a Number” and usually appears when your data has missing or invalid values. … Read more >>
Imagine you’ve just pulled a list of customer email addresses from your database to send out a promotional newsletter. You run the Python script, hit send, and half your customers get the same email twice. That’s the classic duplicate data problem, and it happens more often than you’d think. When you work with real-world data, … Read more >>
Checking whether a Python array contains a value is done with the in operator: Note the vocabulary. What most people call an array, Python calls a list, and in works on both that and a NumPy array. There is no includes() or contains() method. Below: conditions rather than exact values, checking several at once, NumPy … Read more >>
When Python developers say “convert an array to a set”, they often mean converting a list (or a NumPy array) into a Python set so they can remove duplicates or perform fast membership checks. In this tutorial, you will learn several practical ways to convert lists and arrays to sets, understand when each approach is appropriate, and … Read more >>
When you work with real-world data in Python, a common task is to answer questions like: “How many times does this value appear?” Whether you are analyzing survey responses, counting events in logs, or preparing features for machine learning, you often need to count occurrences efficiently and correctly. In this tutorial, you will learn several … Read more >>
If you’ve ever needed to flip rows and columns in your data, converting a 3×4 matrix into a 4×3 one, that’s exactly what transposing an array in Python. In this tutorial, I’ll walk you through five different ways to do it: using NumPy’s transpose() function, the .T shortcut, Python’s built-in zip(), list comprehension, and nested loops. I’ll also cover a … Read more >>
When you work with Python, you constantly need to know how many items you’re dealing with. Maybe you’re validating API responses, counting rows from a CSV, or checking how many images you’re about to process. In this guide, I’ll walk you through the most practical ways to find the number of elements in a “Python … Read more >>
Free PDF · 112 pages
Tell me where to send it and the free 112-page PDF is on its way.
Your free 51 Python Programs PDF is on its way to . Can't find it in a few minutes? Look in your Promotions or Spam folder.