tigertang
tigertang

Skeletal Animation

Interpolation 为什么要讲插值呢？道理是简单的，艺术家们的精力是有限的，他们只能画出有限的关键帧，而关键帧之间的内容需要程序员发挥想象力填充 xD。
tigertang Aug 21, 2018

tigertang Mar 05, 2018

Note on probability and statistics

tigertang Dec 01, 2017

Aftermath队出征啦！ 写在前面 去沈阳赛区是我出的主意。然而我是带了私心的，因为有一个熟识的同学在东北大学，本来想趁着区域赛可以突然去看她。但是到了沈阳之后才发现她并不在区域赛所在的校区，所以只好作罢。不过这并不是重点，重点是清华不参加沈阳赛区的比赛，所以我真正的考虑是在沈阳应该会少一点现场压力，可以一定程度上提升游戏体验（不过还是会被其他学校打爆xD）。
tigertang Oct 30, 2017

Learn Tarjan the hard way

tigertang Sep 13, 2017

KMP是什么？

Prelude prefix[S][l]是$$S$$串的长度为$$l$$的前缀 suffix[S][l]是$$S$$串的长度为$$l$$的后缀 孔乙己：你知道next array的四种写法吗？ next[i]表示什么？ $$nx[i]=max(l)$$，其中$$l$$满足$$prefix[S][l]=suffix[prefix[S][i]][l]$$并且$$l<i$$ 那怎么写呢？容我三思…… 不如先从网上抄个板子一套，反正题目过了就行QAQ
tigertang Sep 05, 2017

Number Theory Review

$axiom:\\ \left.\begin{matrix} g|x\\ g|y\end{matrix}\right\}\Rightarrow \left\{\begin{matrix} g|x\pm y\\ g|xy \end{matrix}\right.\\ \left.\begin{matrix} g|x\\ h|x\\ gcd(g,h)=1 \end{matrix}\right\}\Rightarrow gh|x$
tigertang Aug 25, 2017

Properties of Entropy

Shannon’s theory Theorem: $H(X,Y)\leq H(X)+H(Y)\\ let\ H(X)+H(Y)-H(X,Y)\\ =\sum_{x_{i}}Pr(x_{i})lb(\frac{1}{Pr(x_{i})})+\sum_{y_{j}}Pr(y_{j})lb(\frac{1}{Pr(y_{j})}-H(X,Y))\\ =\sum_{x_{i}}lb(\frac{1}{Pr(x_{i})})\sum_{y_{j}}Pr(x_{i},y_{j})+\sum_{y_{j}}lb(\frac{1}{P(y_{j})})\sum_{x_{i}}Pr(x_{i},y_{j})-H(X,Y)\\ =\sum_{x_{i},y_{j}}Pr(x_{i},y_{j})lb(\frac{1}{Pr(x_{i})Pr(y_{j})})-\sum_{x_{i},y_{j}}Pr(x{i},y_{j})lb(\frac{1}{Pr(x_{i},y_{j})})\\ =\sum_{x_{i},y_{j}}Pr(x_{i},y_{j})lb(\frac{Pr(x_{i},y_{j})}{Pr(x_{i})Pr(y_{j})})\\ =-\sum_{x_{i},y_{j}}Pr(x_{i},y_{j})lb(\frac{Pr(x_{i})Pr(y_{j})}{Pr(x_{i},y_{j})})\\$
tigertang Apr 02, 2017

Good Will Hunting

As is illustrated in the Chinese edition title(心灵捕手), Sean not only hunts for the good will as a senior psychology professor but also undoes the knot in both Will’s and his heart. After reviewing the movie the third time, some fantastic lines and dialogues linger in my mind for such a long time that I chewed them over and over without languor. Definitely Will’s marvelous talents in history, mathematics, literature and even organic chemistry can never be denied. He can defeat MIT professors in mathematics proof without any tough endeavor. He has the capability to quote large quantities of authentic literature to argue with Harvard students and ridicule them with the sentence “The education you got with fifteen thousand is accessible to those pay one point five to go to the public library”.
tigertang Mar 28, 2017

FFT

tigertang Feb 20, 2017