SEARCH KEYWORD -- DATA SCIENCE



  Data as code

What is a good command line parser API? A good command line parser should consider below 5 aspects: Support convenient help information generation Support sub commands, for example, git has push,pull,commit sub commands. Support single character option, word option, flag option and option with parameter. Support default option, for example, if no -port is set, set it as 5037 Support usage model, for example, tar's -c and -x is mutually exclusive, they belong to different usage models. Here are...

   Command line,API     2013-08-08 22:40:36

  Using public key authentication in SSH

SSH is a popular cryptographic network protocol for secure network service operation. It is frequently used in remote server login. For a system administrator or software developer, SSH is frequently used to access remote servers or development servers or testing servers etc.  To login with SSH, there are different authentication mechanisms : password, public key and interactive etc. If a remote server needs to be accessed frequently, password authentication may be too troublesome as p...

   LINUX,DEBUG,SSH,PUBLIC KEY     2016-09-10 05:55:46

  It makes nothing but sense...Mobile Payment...

Chinese New Year is around the corner, every place in China and lots of places in the work have been in the CNY mode. People are rushing out to get all the stuff ready to welcome the New Year Eveand the Spring Festival. I also packed my stuff and flew back to my howntown in China to enjoy the great moment to stay with families and hang out with friends whom I have't been seeing for almost one year. I am exited... However, the first thing stunned me is not my friends but the mobile payment s...

   CHINA,WECHAT PAY,ALIPAY,MOBILE PAYMENT     2018-02-12 00:07:46

  Select top 3 values from each group in a table with SQL

Yesterday, my friend Liu Bing asked me a question about how to select top 3 values for each person in a database table using SQL. I think this question is interesting and it deserves some thoughts. Here I record down how to solve this issue. Assume we have a table which has two columns, one column contains the names of some people and the other column contains some values related to each person. One person can have more than one value. Each value has a numeric type. The question is we want to se...

   SQL,Correlated query,top 3     2013-05-23 03:21:25

  Guide to use Compass

Sass is one kind of CSS Preprocessor, it can make CSS development simple and maintainable. But to show its real power we may need to have Compass. This article is to introduce Compass. Once you learn Compass, your CSS development efficiency will be largely improved. Here we assume you have mastered the major uses of CSS, if you know Sass, then it's better. It's still ok if you don't know Sass. 1. What is Compass? In simple, Compass it the toolkit of Sass. Sass itself is only a compiler, Compass...

   Compass,CSS,Sass,Tutorial     2012-12-03 13:35:46

  Recover deleted file in Linux EXT3 file system

Environment : CentOS 5.3 x86_64, /dev/sdb1 is the data segment /data0. EXT3 file system. Problem : /data0/tcsql/cankao/phpcws-1.5.0/httpcws.cpp is deleted mistakenly and httpcws.cpp is not backed up. It will take much time to rewrite this program again. So we must recover it back. debugfs is feasible in EXT2 file system, but in EXT3 file system, it's not very useful. There is one open source software called ext3grep which can help us recover deleted file in EXT3 file system. The recovery steps a...

   Linux,EXT3,File recovery     2013-08-16 07:06:45

  What to Know About Windows 11

Windows 11 launched in October, with Microsoft bringing some changes to the operating system. It was the first name change in six years, and the rollout began on October 5. The rollout is being phased on eligible devices.  You can download it if you don’t want to wait for it to be your device’s turn.  Some businesses are opting to defer upgrades to Windows 11, as are some individuals. Others are excited to take advantage. The following are some things to know about impleme...

   MICROSOFT,WINDOWS 11     2021-12-06 10:41:04

  Books for entry level C programmers

In computing, C is a general-purpose programming language initially developed by Dennis Ritchie between 1969 and 1973 at Bell Labs Its design provides constructs that map efficiently to typical machine instructions, and therefore it found lasting use in applications that had formerly been coded in assembly language, most notably system software like the Unix computer operating system.To learn C, we need to read many C books and have many practices. Here we summarize a list of C books which may h...

   C,Book,Beginning     2012-07-26 14:00:51

  Google is developing advanced programming technology to simplify Web application development

Beijing, March 28. According to foreign media reports, Google engineer Alex Russell this week at EclipseCon meeting said the company is now developing lots of advanced programming techniques to simplify Web application development.Russell said, "Web development has come to a critical point, it is becoming a run-time library integration platform." Although Web is very popular compared to some platforms such as Java or Windows, it provides only a relatively original programming capability. A ...

   Google,Web,Dart,Scalability     2012-03-30 06:22:13

  Screen recording in Windows 10

Have you ever wondered how to take screen recording easily on Windows? Normally you would think to download some software online and install it on your machine such as Camtasia. However, many of them are either non-free or uneasy to use. Fortunately, there is a built-in tool provided in Windows 10 which can be used to take simple screen recording plus audio recording. The tool is called the Game Bar which is primarily intended for gamers to take screenshots of their plays and achievements. Don't...

   WINDOWS 10,GAME BAR,SCREEN RECORDING     2018-03-06 11:42:07