##### Comparison of DAG-based cryptocurrencies
###### 30 Jan 2019

The linear data structure highly constrains the performance of blockchain. Let’s forget about the Bitcoin bottlenecks like its 1MiB/10min constraint for now. Imagine we’re designing a high-performance payment system. If users are only allowed to append transactions/blocks when they have the latest whole ledger, plenty of time would be wasted in communicating and ensuring their ledger synchronised, and therefore can’t reach a throughput as...

##### Typesetting software documents with LaTeX and PlantUML
###### 21 Oct 2015

Most programmers would agree that coding is preferable over WYSIWYG editing, no matter it’s a webpage or printed matter. When I write a software document, I usually use LaTeX. But when it comes to the diagrams in that document, especially the UML diagrams, I had to use a WYSIWYG editors such as Microsoft Visio. Finally, I had to make the diagrams in a graphic...

##### Machine learning: regularization
###### 27 Jul 2015

This is a lecture note about regularization.

##### Machine learning: logistic regression
###### 25 Jul 2015

This is a lecture note about logistic regression.

##### Machine learning: linear regression
###### 24 Jul 2015

This is a lecture note about linear regression.

##### Matroid
###### 03 Jul 2015

This is a lecture note about matroid, greedy algorithm, and graph theory.

##### Two Prolog solutions to TSP
###### 07 Jan 2015

I’m posting these code here because I can not find a briefer solution.