實現最優二叉樹的構造;在此基礎上完成哈夫曼編碼器與譯碼器。 假設報文中只會出現如下表所示的字符:
字符 A B C D E F G H I J K L M N
頻度 186 64 13 22 32 103 21 15 47 57 1 5 32 20 57
字符 O P Q R S T U V W X Y Z , .
頻度 63 15 1 48 51 80 23 8 18 1 16 1 6 2
要求完成的系統應具備如下的功能:
1.初始化。從終端(文件)讀入字符集的數據信息,。建立哈夫曼樹。
2.編碼:利用已建好的哈夫曼樹對明文文件進行編碼,并存入目標文件(哈夫曼碼文件)。
3.譯碼:利用已建好的哈夫曼樹對目標文件(哈夫曼碼文件)進行編碼,并存入指定的明文文件。
4.輸出哈夫曼編碼文件:輸出每一個字符的哈夫曼編碼。
pashload是應用在linux下的網絡帶寬測試源程序精確度比較高
/////////////////////////////////////
Pathload is a tool for estimating the available bandwidth
of an end-to-end path from a host S (sender) to a host R (receiver).
The available bandwidth is the maximum IP-layer
throughput that a flow can get in the path from S to R,
without reducing the rate of the rest of the traffic in the path.
This handbook is a concise guide to architecting, designing, and building J2EE applications. It guides technical architects through the entire J2EE project, including identifying business requirements, performing use-case analysis, doing object and data modeling, and leading a development team through construction. Whether you are about to architect your first J2EE application or are looking for ways to keep your projects on-time and on-budget, you will refer to this handbook again and again.
The Rails Cookbook is is packed with the solutions you need to be a proficient developer with Rails, the leading framework for building the new generation of Web 2.0 applications. Recipes range from the basics, like installing Rails and setting up your development environment, to the latest techniques, such as developing RESTful web services.
Topics include:
. Modeling data with the ActiveRecord library
. Setting up views with ActionView and RHTML templates
. Building your application s logic into ActionController
. Testing and debugging your Rails application
. Building responsive web applications using JavaScript and Ajax
. Ensuring that your application is security and performs well
. Deploying your application with Mongrel and Apache
. Using Capistrano to automate deployment
. Using the many Rails plugins
Working with graphics
ofdm信道特性
Channel transmission simulator
Channel transmission simulator
%
% inputs:
% sig2 - noise variance
% Mt - number of Tx antennas
% Mr - number of Rx antennas
% x - vector of complex input symbols (for MIMO, this is a matrix, where each column
% is the value of the antenna outputs at a single time instance)
% H - frequency selective channel - represented in block-Toeplitz form for MIMO transmission
% N - number of symbols transmitted in OFDM frame
%
% outputs:
% y - vector of channel outputs (matrix for MIMO again, just like x matrix)
% create noise vector sequence (each row is a different antenna, each column is a
% different time index) note: noise is spatially and temporally white
MT: windows NT/2000/XP command line tape manipulation
written to format a tape windows-XP backup refused to write or format... and satisfy my curiosity
Can be used for crude data recovery (combine seek and read)
UML指南An important part of the Unified Modeling Language (UML) is the facilities for drawing use case
diagrams. Use cases are used during the analysis phase of a project to identify and partition system
functionality. They separate the system into actors and use cases.