XAMPP

Environment

1. Mac + Eclipse
2. Before building the program, we need to prepare the related open-source classes, likes,
   • Apache HttpComponents 4.5 (Supply HTTP interface, submit the HTTP requires to the Target URL, so as to obtain the web’s content. )
   • HTML Parser 2.0 (Used to parser website, to extract url links from DOM nodes)
   • MySQL Connector/J 5. 1.38 (Connect the Java with MySQL, then you can use java code to operate the database. )

Apache Server

• Start up Apache on Mac
  • sudo apachectl (-k) start
  • //sudo apachectl (-k) restart
  • sudo apachectl (-k) stop
• Check the apache version
  • sudo apachectl -v
  • or apachectl -v
• (Mac) Apache: You don’t have permission to access / on this server

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  <Directory "/Users/andy/Sites/"> AllowOverride All Options Indexes MultiViews FollowSymLinks Require all granted </Directory>

1. Introduction of L-BFGS

L-BFGS(Limited-Memory BFGS)是BFGS算法在受限内存时的一种近似算法，BFGS是数学优化中一种无约束最优化算法。links

2. Optimization algorithm - BFGS

BGFS是一种准牛顿算法, 所谓的”准”是指牛顿算法会使用Hessian矩阵来进行优化, 但是直接计算Hessian矩阵比较麻烦, 所以很多算法会使用近似的Hessian, 这些算法就称作准牛顿算法(Quasi Newton Algorithm).

The Details description can refer to the notes

Java multi-threading implementation ways mainly contain three:

• Inherit the “Thread class”
• Realized the “Runnable interface”
• ExecutorService, Callable, Future
  • The former two ways have no return value after the thread execution, only the last one is with a return value.

Thread

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public class MyThread extends Thread{
    public void run(){
      # do something
    }
}

MySQL Installation on Mac

In the newest version of MySQL or later one, it has not need to install the startup item “MySQL_StartupItem.pkg”, also use the default password as “root any more. After installed, Pop-up prompts a temporary password, as the message says:

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2016-03-08T15:35:58.686693Z 1 [Note] A temporary password is generated for root@localhost: E%*oVnN?d7sx
If you lose this password, please consult the section How to Reset the Root Password in the MySQL reference manual.