Pandas: one-column Boolean DataFrame vs Boolean Series

February 15, 2019 1 minute read

Caution when you apply any or all on a one-column Boolean DataFrame, or you should never apply these 2 functions to such a DataFrame because it works differe...

Quick facts on SNAP / Node2vec cannot handle multi-graphs

February 12, 2019 2 minute read

1. Quick Facts On SNAP

Python: pass-by-reference

February 6, 2019 less than 1 minute read

再次提出这个问题是因为遇到了一个 “想在 function 中修改 list 内容” 的场景，而正确的写法应该是用 slice-then-assign:

PCA: my interpretation

January 22, 2019 2 minute read

合着按着我自己的思路才是最好理解的。PCA 的整个过程其实就是：寻找一个基变换 (change of basis)，使得新坐标系内的 axes 的功效可以量化。这个量化的意思是，如果新坐标系内有 x’-axis 和 y’-axis，我可以明确地写出 $\frac{\operatorname{effect}(\te...

Matrix Rank / Row Linear Dependence / λ = 0 / |A| = 0 / Size of Nullspace (Kernel)

January 21, 2019 2 minute read

1. Matrix Rank

Terminology Recap: DNase / DHS / Dnase-seq

January 15, 2019 1 minute read

DNase I

Terminology Recap: ChIP / ChIP-on-chip (ChIP-chip) / ChIP-seq

January 15, 2019 1 minute read

ChIP

R: Quasiquotation

November 30, 2018 5 minute read

1. An example of statement evaluation

R: dive into types

November 30, 2018 5 minute read

1. 预备知识：class() / typeof() / mode() / storage.mode() 2. 预备知识：R Basic Types 总览 3. 深入 Language Objects 4. 深入 Function Types

Digest of R for Data Science

November 29, 2018 26 minute read