﻿<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:trackback="http://madskills.com/public/xml/rss/module/trackback/" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/"><channel><title>C++博客-The Sun Also Rises-随笔分类-Computer Science</title><link>http://www.cppblog.com/FreePeter/category/7079.html</link><description>Algorithm, Mathematica, 计算机科学, C++, photography, GNU/Linux的讨论空间</description><language>zh-cn</language><lastBuildDate>Sun, 29 Jun 2008 05:54:30 GMT</lastBuildDate><pubDate>Sun, 29 Jun 2008 05:54:30 GMT</pubDate><ttl>60</ttl><item><title>代数结构与数理逻辑</title><link>http://www.cppblog.com/FreePeter/archive/2008/06/27/54817.html</link><dc:creator>FreePeter</dc:creator><author>FreePeter</author><pubDate>Fri, 27 Jun 2008 09:25:00 GMT</pubDate><guid>http://www.cppblog.com/FreePeter/archive/2008/06/27/54817.html</guid><wfw:comment>http://www.cppblog.com/FreePeter/comments/54817.html</wfw:comment><comments>http://www.cppblog.com/FreePeter/archive/2008/06/27/54817.html#Feedback</comments><slash:comments>1</slash:comments><wfw:commentRss>http://www.cppblog.com/FreePeter/comments/commentRss/54817.html</wfw:commentRss><trackback:ping>http://www.cppblog.com/FreePeter/services/trackbacks/54817.html</trackback:ping><description><![CDATA[先列两本书，有空的话暑假想扫一下。<br>都没怎么读过，不保证是好书～～～等我扫完了再决定是否推荐～～～<br><br>《近世代数概论》<br><a  href="http://www.douban.com/subject/2152447/">http://www.douban.com/subject/2152447/</a><br>对这本书看着顺眼的原因是当时扫了一下，发现他涵盖了目前为止所有的代数学知识（线性代数等）<br>感觉其线性代数部分比我们学的要难，但又不像数学系的《高等代数》那样过多东东。<br>总得说来是代数学的通论。<br>配合一下那本《数学分析原理》，看起来很完美～～～<br><br>《数理逻辑》 <br><a  href="http://www.douban.com/subject/1729578/">http://www.douban.com/subject/1729578/</a><br>还没读过，有空扫一下。<br>我实在是不理解为什么我们的数理逻辑要用泛代数来引入，其实本质上构造自由代数的过程就是数理逻辑的递归定义过程。<br>我承认构造自由代数的方式确实是个很漂亮的想法，但问题是，数理逻辑应该是最基本的体系吧（类似于集合论），它的用途是 1. 严密化直觉想法 2. 构造一套让计算机来思考的系统。<br>对于(1)来说，拿泛代数来引入就很有问题，类似于用高等的东西论证最基本的东西，就好像我们拿现有的计算机来定义Turing Machine&#8230;&#8230;而且我觉得泛代数在很大程度上分散了我们的注意力&#8230;&#8230;。。。@_@<br>我记得《应用逻辑》中是使用表达式树来引入的，然后还是有一些关于表达式树的形式话定义和一些&#8220;看上去很显然&#8221;的东东的证明的。基本上严密性还是得到保证的（其实本质上也是一个递归定义）。可惜那本书的重点不是传统逻辑（你看名字都叫《应用逻辑》了是吧～）<br><br><br>考完试，终于可以把那本书给扔了。。。啦啦啦～～～<br>个人觉得对Mathematicas in Computer Science比Pure Mathematicas有爱的多。。。不知道为什么。。。@_@<br><br><br><img src ="http://www.cppblog.com/FreePeter/aggbug/54817.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.cppblog.com/FreePeter/" target="_blank">FreePeter</a> 2008-06-27 17:25 <a href="http://www.cppblog.com/FreePeter/archive/2008/06/27/54817.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>两次死在char vs unsigned char上。。。</title><link>http://www.cppblog.com/FreePeter/archive/2008/05/29/51526.html</link><dc:creator>FreePeter</dc:creator><author>FreePeter</author><pubDate>Thu, 29 May 2008 14:31:00 GMT</pubDate><guid>http://www.cppblog.com/FreePeter/archive/2008/05/29/51526.html</guid><wfw:comment>http://www.cppblog.com/FreePeter/comments/51526.html</wfw:comment><comments>http://www.cppblog.com/FreePeter/archive/2008/05/29/51526.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.cppblog.com/FreePeter/comments/commentRss/51526.html</wfw:commentRss><trackback:ping>http://www.cppblog.com/FreePeter/services/trackbacks/51526.html</trackback:ping><description><![CDATA[闭上眼睛写了个<br>int val = 0;<br>for (int i = 0; i &lt; 4; ++i) val = (val &lt;&lt; 8) | x[i];<br>其中x是char[]。<br>问题就在，当x[i]的符号位是1的时候，位扩展为int就全部pad 1了。。。<br>囧死。。。调了半天。。。<br><br><img src ="http://www.cppblog.com/FreePeter/aggbug/51526.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.cppblog.com/FreePeter/" target="_blank">FreePeter</a> 2008-05-29 22:31 <a href="http://www.cppblog.com/FreePeter/archive/2008/05/29/51526.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>Amguity of CFG is undecidable</title><link>http://www.cppblog.com/FreePeter/archive/2008/05/18/50290.html</link><dc:creator>FreePeter</dc:creator><author>FreePeter</author><pubDate>Sun, 18 May 2008 08:30:00 GMT</pubDate><guid>http://www.cppblog.com/FreePeter/archive/2008/05/18/50290.html</guid><wfw:comment>http://www.cppblog.com/FreePeter/comments/50290.html</wfw:comment><comments>http://www.cppblog.com/FreePeter/archive/2008/05/18/50290.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.cppblog.com/FreePeter/comments/commentRss/50290.html</wfw:commentRss><trackback:ping>http://www.cppblog.com/FreePeter/services/trackbacks/50290.html</trackback:ping><description><![CDATA[reduce to PCP~~~<br><br><a title="http://people.cis.ksu.edu/~rhowell/770s03/lectures/23-twoup.pdf" href="http://www.google.com/history/url?url=http://people.cis.ksu.edu/%7Erhowell/770s03/lectures/23-twoup.pdf&amp;ei=l-gvSPb5IpnyqgPFg-HiCg&amp;sig2=PXzaJR02IH_rzNqTo-ZpAA&amp;ct=h" id="bkmk_href_9" dir="ltr">http://people.cis.ksu.edu/~rhowell/770s03/lectures/23-twoup.pdf</a>&nbsp;
<br><br><br><img src ="http://www.cppblog.com/FreePeter/aggbug/50290.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.cppblog.com/FreePeter/" target="_blank">FreePeter</a> 2008-05-18 16:30 <a href="http://www.cppblog.com/FreePeter/archive/2008/05/18/50290.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>搜到一个比较好玩的东西，design of double precision IEEE-754, Floating-Points Units</title><link>http://www.cppblog.com/FreePeter/archive/2008/05/17/50182.html</link><dc:creator>FreePeter</dc:creator><author>FreePeter</author><pubDate>Sat, 17 May 2008 12:44:00 GMT</pubDate><guid>http://www.cppblog.com/FreePeter/archive/2008/05/17/50182.html</guid><wfw:comment>http://www.cppblog.com/FreePeter/comments/50182.html</wfw:comment><comments>http://www.cppblog.com/FreePeter/archive/2008/05/17/50182.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.cppblog.com/FreePeter/comments/commentRss/50182.html</wfw:commentRss><trackback:ping>http://www.cppblog.com/FreePeter/services/trackbacks/50182.html</trackback:ping><description><![CDATA[<a href="http://www.scribd.com/doc/247203/Design-of-Double-Precision-IEEE754-FloatingPoint-Units">http://www.scribd.com/doc/247203/Design-of-Double-Precision-IEEE754-FloatingPoint-Units</a><br><br>看到了熟悉的Gate &amp;&amp; MUX...<br>anyway...个人对底层这块不是特别灵。。。~~~<br><br>p.s. ms是一个可以上传pdf的网站？.~~~<br><br> <img src ="http://www.cppblog.com/FreePeter/aggbug/50182.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.cppblog.com/FreePeter/" target="_blank">FreePeter</a> 2008-05-17 20:44 <a href="http://www.cppblog.com/FreePeter/archive/2008/05/17/50182.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item></channel></rss>