上下文无关文法（Context-Free Grammar, CFG）是一个4元组G=(V, T, S, P)，其中，V和T是不相交的有限集，S∈V，P是一组有限的产生式规则集，形如A→α，其中A∈V，且α∈(V∪T)*。V的元素称为非终结符，T的元素称为终结符，S是一个特殊的非终结符，称为文法开始符。 设G=(V, T, S, P)是一个CFG，则G产生的语言是所有可由G产生的字符串组成的集合，即L(G)={x∈T* | Sx}。一个语言L是上下文无关语言（Context-Free Language, CFL），当且仅当存在一个CFG G，使得L=L(G)。 *⇒ 例如，设文法G：S→AB A→aA|a B→bB|b 则L(G)={a^nb^m | n,m>=1} 其中非终结符都是大写字母，开始符都是S，终结符都是小写字母。
标签： Context-Free Grammar CFG
上传时间： 2013-12-10
上传用户：gaojiao1999
《CODE READING》配套书源代码 《CODE READING》配套书源代码
上传时间： 2014-01-10
上传用户：思琦琦
This code was used for making the practical measurements in section 2.3 of my thesis. This Matlab code allows an OFDM signal to be generated based on an input data file. The data can be random data, a grey scale image, a wave file, or any type of file. The generated OFDM signal is stored as a windows wave file, allowing it to be viewed, listened to and manipulated in other programs. The modified wave file can then be decoded by the receiver software to extract the original data. This code was developed for the experiments that I performed in my honours thesis, and thus has not been fully debugged. This is the original code developed for the thesis and so has several problems with it. The BER performance given by the simulations is infact Symbol Error Rate.
标签： This measurements practical section
上传时间： 2015-09-20
上传用户：tedo811
This code in this directory implements the binary hopfield network. Source code may be found in HOPNET.CPP. A sample training file is H7x8N4.trn. Sample test pattern files are: H7x8D4.TST, H5x8D7.TST, H5x8D7.TST and H5x8D9.TST, Output of the program goes to both the screen and a file, ARCHIVE.LST.
标签： code implements directory hopfield
上传时间： 2014-01-16
上传用户：123啊
Code for VB.NET教程源码 很好的源码，希望对你有所帮助。
上传时间： 2014-12-05
上传用户：bjgaofei
dsp 生成spwm的源代码上传一份完整的SPWM code in C,旨在提高国人的设计水平
上传时间： 2015-09-21
上传用户：天诚24
USB application source code with Philips USB chip set D12 on microcontroller
标签： microcontroller application USB Philips
上传时间： 2015-09-21
上传用户：yuchunhai1990
编码源程序,清华版本的,tmn-1.7 H.263 video frequency code source program, Qinghua edition ,C-C++
标签： frequency Qinghua edition program
上传时间： 2013-12-09
上传用户：as275944189
nRF24E1 sample sensor node code
上传时间： 2014-09-04
上传用户：zhaoq123
.data val1 sword 0 val sword -276 .code main proc mov ax,val cwd mov bx,10 idiv bx mov val1,ax call writebin call crlf mov ax,dx call writebin exit main endp end main
上传时间： 2015-09-21
上传用户：wlcaption
