# Page Not Found

The URL `7-1` does not exist. This page may have been moved, renamed, or deleted.

## Suggested Pages

You may be looking for one of the following:
- [7-1](https://windmising.gitbook.io/liu-yu-bo-play-with-machine-learning/src/chapter7-1/7-1.md)
- [第六章：梯度下降法](https://windmising.gitbook.io/liu-yu-bo-play-with-machine-learning/src/chapter6/6-1.md)
- [主成分分析法 PCA Principal Component Analysis](https://windmising.gitbook.io/liu-yu-bo-play-with-machine-learning/src/chapter7/7-0.md)
- [第八章：多项式回归与模型泛化](https://windmising.gitbook.io/liu-yu-bo-play-with-machine-learning/src/chapter8/8-1.md)
- [第九章：逻辑回归](https://windmising.gitbook.io/liu-yu-bo-play-with-machine-learning/src/chapter9/9-1.md)

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### Option 1 — Ask a question (recommended)

Perform an HTTP GET request on the documentation index with the `ask` parameter:

```
GET https://windmising.gitbook.io/liu-yu-bo-play-with-machine-learning/src/chapter7-1/7-1.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

### Option 2 — Browse the documentation index

Full index: https://windmising.gitbook.io/liu-yu-bo-play-with-machine-learning/sitemap.md

Use this to discover valid page paths or navigate the documentation structure.

### Option 3 — Retrieve the full documentation corpus

Full export: https://windmising.gitbook.io/liu-yu-bo-play-with-machine-learning/llms-full.txt

Use this to access all content at once and perform your own parsing or retrieval. It will be more expensive.

## Tips for requesting documentation

Prefer `.md` URLs for structured content, append `.md` to URLs (e.g., `/liu-yu-bo-play-with-machine-learning/src/chapter7-1/7-1.md`).

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