update files

README.md

@@ -1,17 +1,19 @@
 # 📊 DataScience Learning Hub
 
-Welcome to a comprehensive collection of educational web projects for learning data science! This repository contains multiple interactive courses and resources covering statistics, machine learning, visualization, mathematics, and feature engineering.
+Welcome — a small collection of interactive, static web projects for learning statistics, machine learning, visualization and maths. Each project is a standalone static site you can open directly in the browser or serve with a tiny static server.
 
-## 🎯 Live Demos
+## 🎯 Quick access (deployed + local)
 
-Visit our courses directly in your browser:
+Below are direct links you can use after deploying the repository to GitHub Pages (or any static host). Each also shows the local/relative path you can use while previewing from the repo root.
 
-- [📈 Interactive Statistics Course](https://aashishgarg13.github.io/DataScience/complete-statistics/)
-- [🤖 Machine Learning Guide](https://aashishgarg13.github.io/DataScience/ml_complete-all-topics/)
-- [📊 Data Visualization](https://aashishgarg13.github.io/DataScience/Visualization/)
-- [🔢 Mathematics for Data Science](https://aashishgarg13.github.io/DataScience/math-ds-complete/)
-- [⚙️ Feature Engineering Guide](https://aashishgarg13.github.io/DataScience/feature-engineering/)
-- [🤔 Prompt Engineering Guide](https://learnprompting.org/) - Interactive AI prompting course
+GitHub Pages base: https://aashishgarg13.github.io/DataScience/
+
+- 📈 Interactive Statistics Course — Deployed: https://aashishgarg13.github.io/DataScience/complete-statistics/  | Local: `complete-statistics/`
+- 🤖 Machine Learning Guide — Deployed: https://aashishgarg13.github.io/DataScience/ml_complete-all-topics/  | Local: `ml_complete-all-topics/`
+- 📊 Data Visualization — Deployed: https://aashishgarg13.github.io/DataScience/Visualization/  | Local: `Visualization/`
+- 🔢 Mathematics for Data Science — Deployed: https://aashishgarg13.github.io/DataScience/math-ds-complete/  | Local: `math-ds-complete/`
+- ⚙️ Feature Engineering Guide — Deployed: https://aashishgarg13.github.io/DataScience/feature-engineering/  | Local: `feature-engineering/`
+- [🤔 Prompt Engineering Guide](https://aashishgarg13.github.io/DataScience/prompt-engineering-guide/) - Interactive AI prompting course
 
 ## 🔗 Prompt Engineering Resources
 
@@ -76,83 +78,62 @@ The repository supports automatic updates for:
 - Additional learning resources and examples
 - Community contributions and fixes
 
-## 🚀 Quick Start
-
-### Option A: View Online
-Visit our GitHub Pages hosted versions:
-1. [Statistics Course](https://aashishgarg13.github.io/DataScience/complete-statistics/)
-2. [Machine Learning Guide](https://aashishgarg13.github.io/DataScience/ml_complete-all-topics/)
-
-### Option B: Run Locally (Recommended for Development)
-
-#### Simple Browser Opening:
-1. Clone this repository
-2. Navigate to either project folder
-3. Double-click `index.html`
+## 🚀 Try locally (quick)
 
-#### Using Local Server (Recommended to avoid CORS issues):
+Option A — open a project's `index.html` directly from Finder (double-click the file). Some interactive features are more reliable when served via HTTP.
 
-From the repository root, run one of the following in a terminal:
+Option B — serve the repo root with a tiny static server (recommended):
 
 ```bash
-# Python 3 (simple static server, available on macOS):
+# from repository root
 python3 -m http.server 8000
 
-# or using Node.js http-server (if installed):
-npx http-server -c-1 . 8000
+# then open one of these in your browser (example):
+http://localhost:8000/complete-statistics/
+http://localhost:8000/ml_complete-all-topics/
+http://localhost:8000/Visualization/
+http://localhost:8000/math-ds-complete/
+http://localhost:8000/feature-engineering/
 ```
 
-Then open http://localhost:8000/complete-statistics/ or http://localhost:8000/ml_complete-all-topics/ in your browser.
+Tip: Using a local server avoids browser file:// restrictions (CORS, modules, etc.) and ensures the JS visualizations behave the same as on a real host.
 
-## Deploy to GitHub Pages
+## 📦 Deploy (GitHub Pages)
 
-1. Push your changes to the `main` branch on GitHub (already done for this repo).
-2. In your repository settings on GitHub, go to "Pages" and select the `main` branch and root (`/`) as the source, or set the `gh-pages` branch if you prefer.
-3. Save — GitHub Pages will publish the site. For multi-site repos you can add a `docs/` folder or create separate branches, or create a small repo per site.
+1. Push `main` to GitHub.
+2. In the repo on GitHub → Settings → Pages, set the Source to the `main` branch and the folder to `/ (root)`.
+3. Save and wait a few minutes; your projects will be available under:
 
-Because these are static sites you can also host them on Netlify, Vercel, or any static host.
+`https://<your-username>.github.io/DataScience/<folder>/` (for example the links above).
 
-## 📁 Project Structure
+Note: these projects use relative paths for assets (`style.css`, `app.js`), so they work correctly when served from a subpath such as `/DataScience/complete-statistics/`.
+
+## 📁 Project structure (example)
 
-### Statistics Course
-```
 complete-statistics/
-├── index.html  # Main course interface
-├── style.css   # Course styling
-└── app.js      # Interactive visualizations
-```
+- `index.html` — main course interface
+- `style.css`
+- `app.js`
 
-### Machine Learning Guide
-```
 ml_complete-all-topics/
-├── index.html  # Main guide interface
-├── style.css   # Guide styling
-└── app.js      # Interactive components
-```
+- `index.html` — machine learning guide
+- `style.css`
+- `app.js`
 
-### Data Visualization
-```
 Visualization/
-├── index.html  # Visualization examples
-├── style.css   # Visualization styling
-└── app.js      # Interactive charts
-```
+- `index.html` — visualization examples
+- `style.css`
+- `app.js`
 
-### Mathematics for Data Science
-```
 math-ds-complete/
-├── index.html  # Mathematics course interface
-├── style.css   # Course styling
-└── app.js      # Interactive math demonstrations
-```
+- `index.html` — mathematics for data science
+- `style.css`
+- `app.js`
 
-### Feature Engineering Guide
-```
 feature-engineering/
-├── index.html  # Feature engineering guide
-├── style.css   # Guide styling
-└── app.js      # Interactive examples
-```
+- `index.html` — feature engineering notes and demos
+- `style.css`
+- `app.js`
 
 ## Notes about repository cleanup
 
@@ -166,15 +147,15 @@ While repairing the repository I removed macOS Finder metadata files (names begi
 
 If you want to inspect any backup I created of the original `.git`, look for directories named `.git.broken_<timestamp>` in the repository root — they contain the backed-up git metadata.
 
-## 🤝 Contributing
+## 🤝 Contributing & improvements
+
+Helpful things you can do:
 
-This project welcomes contributions! Here's how you can help:
+- Add screenshots or small thumbnails for each project folder (I can add these if you provide images).
+- Add a `CONTRIBUTING.md` if you want contribution rules or a PR checklist.
+- Add an automated `scripts/verify_assets.py` that checks every `href/src` referenced by `index.html` files and reports missing assets — I can add this for you.
 
-1. **Content Improvements**
-   - Add new interactive examples
-   - Improve existing visualizations
-   - Update documentation and guides
-   - Share prompt engineering techniques
+Tell me which of these you'd like and I'll implement it.
 
 2. **Technical Enhancements**
    - Optimize JavaScript performance

ml_complete-all-topics/app.js

@@ -148,26 +148,43 @@ function initSections() {
 // Smooth scroll for TOC links
 function initTOCLinks() {
   const links = document.querySelectorAll('.toc-link');
-  
+
   links.forEach(link => {
+    const href = link.getAttribute('href');
+    // Only attach handler for hash links
+    if (!href || !href.startsWith('#')) return;
+
     link.addEventListener('click', (e) => {
       e.preventDefault();
-      const targetId = link.getAttribute('href').substring(1);
+
+      const targetId = href.substring(1);
       const target = document.getElementById(targetId);
-      
-      if (target) {
-        // Remove active from all links
+
+      if (!target) {
+        // target not present in DOM; warn and do nothing
+        console.warn(`TOC link clicked but target not found: #${targetId}`);
+        return;
+      }
+
+      try {
+        // Remove active from all links and mark this one
         links.forEach(l => l.classList.remove('active'));
         link.classList.add('active');
-        
-        // Scroll to target
-        target.scrollIntoView({ behavior: 'smooth', block: 'start' });
-        
-        // Expand the section
-        const toggle = target.querySelector('.section-toggle');
+
+        // Smooth scroll to the section
+        if (typeof target.scrollIntoView === 'function') {
+          target.scrollIntoView({ behavior: 'smooth', block: 'start' });
+        } else {
+          window.location.hash = '#' + targetId;
+        }
+
+        // Expand the section body if present (guarded)
         const body = target.querySelector('.section-body');
-        body.classList.add('expanded');
-        toggle.classList.remove('collapsed');
+        const toggle = target.querySelector('.section-toggle');
+        if (body && body.classList) body.classList.add('expanded');
+        if (toggle && toggle.classList) toggle.classList.remove('collapsed');
+      } catch (err) {
+        console.error('Error handling TOC link click for #' + targetId, err);
       }
     });
   });