Some Useful Tools

March 13, 2025 · 0 min read

Some useful tools for developers.

Note: This post will be updated regularly.

A Shopping Experience in Pang Donglai Supermarket

March 7, 2025 · 16 min read

前天在广州找朋友时发现附近有一家永辉超市，它是去年年末自主改调的“胖东来”超市，我一下子来了兴致，之前虽然也去过河南很多城市，但是没有去过许昌和新乡(New York)，而胖东来又不在河南之外开店，所以一直缺少体验的机会。在胖东来仔细转了一遍后，我对胖东来的服务有了更进一步的理解和感受。

Langchain and RAG Best Practices

March 5, 2025 · 16 min read

This is a quick-start essay for LangChain and RAG which mainly refers to the Langchain chat with your data^[1] course which are taught by Harrison Chase and Andrew Ng.

Random Walks

February 18, 2025 · 5 min read

This article is a summary of the random walks in the book “Random Processes” by Gregory F. Lawler.

Sequences of Random Variables

February 2, 2025 · 2 min read

Parameter Estimation

February 2, 2025 · 5 min read

This is the notes for the lecture of Parameter Estimation.

Two Random Variables

February 1, 2025 · 0 min read

This article is about the two random variables and their properties.

Further Understanding of Proc

February 1, 2025 · 3 min read

The /proc in Linux is a kind of Pseudo file system (also known as Virtual File System), what it saves is a series of special files that store the current running state of the kernel, and the user can check the hardware info and the runnning processes via the files, even adjust some files to change the state of running kernel. The files in /proc will be refresh in RAM, so the files’ size is 0 bytes.

The Iftop

January 30, 2025 · 1 min read

I frequently use ifconfig and cat /proc/net/dev to examine network information. However, today, my cloud server crashed unexpectedly. I reached out to the cloud support for assistance. The engineer utilized iftop to analyze the situation. After the issue was resolved, I started to consider using this tool. Now, let’s take a closer look at this powerful utility.

Some Useful Commands to Share

January 30, 2025 · 0 min read

Some good commands to share.

Note: This post will be updated regularly.