sigmoid neuron vs PyLearn

This app explains how a single sigmoid neuron works. You can have some insight for neural network.

Real Python, running on your phone. Not quizzes about Python — an editor, an interpreter, and tests that check what your code actually did. Every lesson gives you a problem, a code editor and a Run button. You write Python, run it, and see the output and the failing tests. The interpreter is real CPython, bundled inside the app, so it works on a plane, on the underground, and anywhere else with no signal. WHAT IS IN IT • 12 courses, 108 lessons, from your first variable to shipping an AI system • 27 quizzes and 6 capstone projects, graded against hidden tests • 12 cheatsheets for the things nobody remembers • 12 badges, XP and a streak, for the days when momentum is the hard part THE PATH Start with Python Basics: variables, loops, conditionals, functions. Then data structures, functions and objects, files and errors, data analysis, APIs and async. Then the part most courses stop before: LLM APIs and prompting, structured output and tool calling, embeddings and vector search, RAG systems, agents and tool use, and evals and shipping. Real practice with the things AI engineering is actually made of. NO ACCOUNT NEEDED The app opens and works with no sign-up. Make an account only if you want your progress on more than one device — it syncs when there is a connection and waits patiently when there is not. BUILT FOR A PHONE • A code editor with line numbers, syntax highlighting and a punctuation row, because semicolons and brackets are miserable on a phone keyboard • Adjustable text size everywhere, including inside code • Hints when you are stuck and a worked solution when you have had enough • Dark and light, and it respects the size you read at Python runs entirely on your device — no server executes your code. Signed out, nothing you write leaves the phone at all. With an account, your work syncs so you can carry on somewhere else, and the tutor sees the lesson and your code in order to answer questions about them.