fp-tree and fp-growth in plain english No ratings yet.

The normal use case is to discover interesting relations between variables in large databases, e.g: i(t) 1 ABDE 2 BCE 3 ABDE 4 ABCE 5 ABCDE 6 BCD the above are some transactions, let’s A, B, C … are some products people bought. we want to find which set are frequent set .e.g: BC  is • Read More »



K-means clustering and Bisecting K-means in Plain English No ratings yet.

K-means clustering is unsupervised machine learning algorithm. Wikipedia has a great demo as below on how it works: Demonstration of the standard algorithm 1. k initial “means” (in this case k=3) are randomly generated within the data domain (shown in color). 2. k clusters are created by associating every observation with the nearest mean. The • Read More »



Bison/Yacc cheat sheet ( Parser Generator cheat sheet) No ratings yet.

The same thing happened to bison/yacc, I googled around, and was a little surprised that I could not find a bison/yacc cheat sheet. So I made a very rudimentary one here. Bison-Yacc_cheat_sheet Please comment on how to improve it. References: https://www.gnu.org/software/bison/manual/html_node/index.html Please rate this rating



SVM ( support vecotr machine) in Plain English No ratings yet.

(1) Maximum the margin SVM is very easy to understand on the graph,, we just need to find the  a separate plane which maximum the margin. see the graph below: (2) How to calculate/find the max Margin Assuming hard-margin issue for the simplicity of math, the separate plane can be expressed as: w*x -b = 0  where • Read More »


Quadratic programming in plain English No ratings yet.

The big picture is:  a quadratic programming problem can be reduced to be a linear programming problem. Here is how: (1) KTT conditions For any non-linear programming: max: f(x),  s.t: g(x) <=0 It has been proved that it needs to meet Karush–Kuhn–Tucker (KKT) conditions provided that some regularity conditions are satisfied how it is being proved? it is • Read More »


socat introduction No ratings yet.

While searching a command line to write something into a UNIX Domain Socket, I found this great tool called socat which is similar to netcat/samplicator but has more features. The man page said: Socat is a command line based utility that establishes two bidirectional byte streams and transfers data between them. Because the streams can • Read More »