Posts by Year

2018

快速排序与快速选择算法

less than 1 minute read

之所以突然会对这个问题感兴趣是因为,大概一年前,在毫无准备的情况下去参加某互联网公司的面试,被问到了这样一个问题:“给定一个长度为n的数列,如何快速的找出其中第m大的元素。假设m远小于n。”因为对排序和选择算法完全不熟悉,只知道quicksort的时间复杂度应该是,以及从数列中找出最大值的复杂度是 。只好回答最简...

What Is Random Fourier Features Method?

2 minute read

Random Fourier features method, or more general random features method is a method to help transform data which are not linearly separable to linearly separa...

如何阻止ssh重命名tmux窗口

less than 1 minute read

在使用tmux多窗口终端时,每次登录学校的服务器后,窗口的标签就会被改成与服务器的prompt相同。而且登出后也不会改回来,导致tmux经常几个窗口的名字都很长,也没有反映窗口当时的状况。之所以会这样,是因为tmux默认允许一些进程修改窗口名,而ssh对终端窗口的命名规则是由服务器上的配置文件决定的。

HiDPI Chromebook上Crouton的设置

less than 1 minute read

入手HP Chromebook 13 g1大半年,一开始就安装了Gallium OS。但Gallium OS迟迟无法解决intel skylake model上的音频输出问题,加上Gallium OS的电源管理比Chrome OS要弱不少,不接电源的情况下无法长时间的使用。忍了大半年后,终于回到了Crouton的...

利用Jekyll搭建博客

less than 1 minute read

搭建个人博客主要有三种途径。一种是利用现成的博客网站,如Google的Blogger服务,新浪博客等。另一种则是利用软件生成博客网页, 再上传到自己的服务上。这一类博客生成软件有不少,比如应用最广泛的WordPress,和功能稍弱,但更为简洁的Jekyll和Pelican。

Holder’s and Young’s Inequalities

1 minute read

Classical Case A quick proof of general Holder’s inequality is as follows. First, by Jensen’s inequality, we have for positive and satisfying ,

Log Loss and Multi-Class Hinge Loss (1)

2 minute read

Hinge loss functions are mainly used in support vector machines for classification problem, while cross-entropy loss functions are ubiquitous in neural netwo...

Proof of Stirling’s Formula

less than 1 minute read

Stirling’s formula is very useful in all kinds of asymptotic analysis. Here we present one of many proofs.

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2017

Acer C720电池更换及GalliumOS安装与配置

less than 1 minute read

八月份完成论文的一个主要部分,决定犒赏一下自己。一直以来都想升级一下我的C720,毕竟是4年前的电脑了。特别是电池续航已经大不如从前,系统显示电池满电容量也只有标称容量的一半左右。没有了最初让我惊艳的全天不插电的续航表现,其他方面的弱点就让人更不能忍受了,比如屏幕的大小和分辨率,都距离今天的商务级的dell cp...

Chromebook如何让我变一个Linux粉

less than 1 minute read

昨天花了两个多小时帮室友把他闲置了大半年的Chromebook装上了Linux系统。期间聊起我是什么时候开始接触和使用Linux系统的:

On Hoeffding’s Inequality

1 minute read

Hoeffding inequality was first proved in 1963 for independent bounded random variables. It captures the effect of cancellation among independent random varia...

On No Free Lunch Theorem

1 minute read

This note discusses the implications of the celebrated No-Free-Lunch Theorem on kernel SVM, RF-SVM and neural network.

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2014

How to Update crouton in China

1 minute read

After the latest update of Chrome OS, the audio output had some problem of the ubuntu precise installed on my C720 via crouton. After searching online for ad...

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