The use of * in python is related to the way of passing parameters to a function. First, in python, we have three types of parameters, Positional-or-Keyword Arguments, Positional-Only Parameters an...
Embedding algorithms 1 -- Multidimensional scaling
Manifold learning is a class of unsupervised estimators that seeks to describe datasets as low-dimensional manifolds embedded in high-dimensional spaces. Some linear dimension reduction methods ar...
Mathematical definition of Manifold
The machine learning community has borrowed lots of terminologies from mathematics. To gain a deeper understanding of the feature learning/dimension reduction approaches, I make some notes of the r...
Some useful operations in MySQL--Median level
The second post of SQL includes median level applications. Running total calculation – window function Aggregations/rankings on a subset of rows relative to the current row being transformed by S...
Some useful operations in MySQL--Easy level
I am practicing some SQL question to prepare for 2020 summer intership interviews. I learned some useful operations beyond the basic SELECT, FROM, WHERE, GROUP BY and HAVING. Some useful DATE oper...
Kosaraju's algorithm to find SCCs
Definition of Strongly Connected Components The question addressed in this post is to find the Strongly Connected Components (SCCs) in a directed graph G. These SCCs is a partition of G, which mean...
Dynamic Programming
I am following the free online courses, Algorithms: Design and Analysis, on Stanford Lagnuita to learn Basic CS algorithms. While I am capable of understanding the Part1 fast and smoothly, I paused...
Count inversion with merge sort
Question Given a list of number, how many inversion pairs are there? If the list is [1, 3, 5, 2, 4, 6], there are three inversions: (3, 2), (3, 4), (3, 6). A brute force method would be using two ...