<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[fourier_transformer的博客]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/fourier_transformer</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; fourier_transformer]]></copyright><item><title><![CDATA[vscode下的anaconda环境中import numpy问题]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/107611446</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/107611446</guid><author>fourier_transformer</author><pubDate>Mon, 27 Jul 2020 14:57:50 +0800</pubDate><description><![CDATA[DLL LOAD FAILED &amp;&amp; MKL-SERVICE PACKAGE FAILED TO IMPORT
(我觉得可能只有windows下有这问题)
好长时间了，在vscode搭配anaconda写python的时候，只要import numpy，就会随机出现这样的错误：
import numpy
E:\installed\Anaconda3\lib\site-packages\numpy_init_.py:140: UserWarning: mkl-service package f]]></description><category></category></item><item><title><![CDATA[过半的2020]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/107316821</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/107316821</guid><author>fourier_transformer</author><pubDate>Mon, 13 Jul 2020 14:46:40 +0800</pubDate><description><![CDATA[今天是2020年7月12日，距离上一篇博客发布已经一个多月。这一个多月里，我主要做了以下几件事：

博客系统
玩win10…
用python实现的音频AI技术
大哥说让我看个他们最近开发的项目，理一理架构
大哥说让我找找有没有自动标签生成相关的产品，我就顺便接触了下NLP，看了看介绍，以及关键字生成的一些特征算法
玩了玩python爬虫，爬了实习僧网站。下一步准备结合关键字提取，做一下数据分析，主要目标是找出岗位的主要需求
哦对，还有趁着steam夏促玩了个神作——Outer Wilds

博客系统
首页
]]></description><category></category></item><item><title><![CDATA[Day 1 - 几个疑难小问题]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/106064244</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/106064244</guid><author>fourier_transformer</author><pubDate>Sun, 12 Jul 2020 15:45:18 +0800</pubDate><description><![CDATA[Servlet 404问题
如果你在查看项目路径和url地址之后确认没问题，然而打开servlet仍然是404，以下可能有帮助。
传统方法应该是这么设置servlet程序映射地址的，在web.xml里面加入servlet相关信息，每添加一个servlet类就要加这么一段：
&lt;servlet&gt;
        &lt;servlet-name&gt;ServletDemo&lt;/servlet-name&gt;
        &lt;servlet-class&gt;ServletDemo&l]]></description><category></category></item><item><title><![CDATA[Day2 - Servlet, Response, Request]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/106081047</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/106081047</guid><author>fourier_transformer</author><pubDate>Wed, 10 Jun 2020 16:41:27 +0800</pubDate><description><![CDATA[Day2 - Servlet, Response, RequestServlet1. 简介2. 运行过程Servlet模板一些经常用到的设置程序
以下内容均参考JavaWeb学习总结
Servlet
1. 简介

一种开发动态web资源的技术
实现了Servlet接口的java程序

简单来说，Servlet的作用就是控制Request和Response这两个对象。
2. 运行过程
Servlet程序由Web服务器调用，客户端请求访问Servlet程序后：

Web服务器首先检查是否已经装载该Servlet]]></description><category></category></item><item><title><![CDATA[CS61B - Lec 34 - Quicksort II]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105846226</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105846226</guid><author>fourier_transformer</author><pubDate>Wed, 29 Apr 2020 20:01:30 +0800</pubDate><description><![CDATA[Lec 34 - Quicksort IIQuicksort vs. MergesortQuick SelectStability
前几天把bearmaps搞定了。（其实还是有些不完美的地方不过应该不是我实现的算法的问题。给了一个完整的前端+后端框架，里面有点bug得慢慢研究）刷了刷题，感觉比一个月前要强不少，谢谢josh hug。
啥时候才能找个工作哎。
本章接上回，将具体的partition和...]]></description><category></category></item><item><title><![CDATA[CS61B - Lec33 - Quicksort]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105704750</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105704750</guid><author>fourier_transformer</author><pubDate>Thu, 23 Apr 2020 14:47:40 +0800</pubDate><description><![CDATA[Lec33 - QuicksortBackstory, PartitioningQuicksortQuicksort RuntimeAvoid the Quicksort Worst Case
这一章学习了运用广泛的quicksort，其中运用了分治的思想。
Backstory, Partitioning
Quicksort是在1960年，Tony Hoare在解决一个翻译问题时发明。
有这样一句...]]></description><category></category></item><item><title><![CDATA[CS61B - Lec 32 - Basic Sort]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105678713</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105678713</guid><author>fourier_transformer</author><pubDate>Wed, 22 Apr 2020 17:57:31 +0800</pubDate><description><![CDATA[Lec 32 - Basic SortSorting ProblemSelection Sort and HeapsortMergesortInsertion Sort
今天正式进入phase 3，算法阶段。
Sorting Problem
今天只是个基础所以内容还是很愉快的。排序算法是很多算法的基础，并且分析的过程也可以举一反三，所以作为算法篇的开头。这里主要探讨了排序的几种方式以及优化。
Se...]]></description><category></category></item><item><title><![CDATA[CS61B - Lec 31 - Minimum Spanning Trees]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105633824</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105633824</guid><author>fourier_transformer</author><pubDate>Mon, 20 Apr 2020 15:24:48 +0800</pubDate><description><![CDATA[Lec 31 - Minimum Spanning TreesMST, Cut Property, Generic MST AlgorithmPrim's AlgorithmKruskal's Algorithm
一个Warm-up question: 给定一个graph，判断里面有没有cycle。
方案1：直接遍历，如果遍历到了marked的点，就说明有cycle。需要O(V+E)的复杂度。

...]]></description><category></category></item><item><title><![CDATA[CS61B - Lec 30 - Graph 3 - Shortest Paths]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105614830</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105614830</guid><author>fourier_transformer</author><pubDate>Sun, 19 Apr 2020 18:25:46 +0800</pubDate><description><![CDATA[Lec 30 - Graph 3 - Shortest PathsBFS vs. DFSDijkstra's AlgorithmDijkstra's Correctness and RuntimeA*A* Heuristics(启发式学习)
昨天晚上装了下anaconda，准备开始学语音识别了。不得不说把环境调的顺心如意真是最烦的事情，因为好多东西根本不懂只能一直百度，晕头撞向的。
BFS vs....]]></description><category></category></item><item><title><![CDATA[CS61B - Lec 29 - Graphs2, BFS, DFS]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105596301</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105596301</guid><author>fourier_transformer</author><pubDate>Sat, 18 Apr 2020 17:00:23 +0800</pubDate><description><![CDATA[Lec 29 - Graphs2, BFS, DFSBreadthFirstPathsGraph APIReprensentation and RuntimesGraph Traversal Implementation and Runtime
这一章学了具体怎么实现Graph。
BreadthFirstPaths
BreadthFirst，广度优先，意思就是从根节点开始，遍历完所有到根节点距离相...]]></description><category></category></item><item><title><![CDATA[CS61B - HW3 - Hashing - 溢出问题]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105570733</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105570733</guid><author>fourier_transformer</author><pubDate>Fri, 17 Apr 2020 22:42:33 +0800</pubDate><description><![CDATA[HW3主要做了两件事情：重写equals和hashCode方法。有两个值得注意的点。
equals方法需要满足的条件

所以在重写equals方法时，必须额外考虑null, 其它class这两种特殊情况。
@Override
    public boolean equals(Object o) {
        if (o == this) return true;
        if (o...]]></description><category></category></item><item><title><![CDATA[CS61B - Lec28 - Intro to Graphs]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105584381</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105584381</guid><author>fourier_transformer</author><pubDate>Fri, 17 Apr 2020 18:58:32 +0800</pubDate><description><![CDATA[Lec28 - Intro to GraphsTrees and TraversalsGraphsGraph ProblemsDepth-First Traversal
今天学习了新的结构——Graph，是更广义上的Tree（Tree∈Graph)。
Trees and Traversals
这一节讲了之前提到的Tree的遍历方式（Traversals)——preorder, inorder, p...]]></description><category></category></item><item><title><![CDATA[CS61B - Lec 27 - kd Tree]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105557971</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105557971</guid><author>fourier_transformer</author><pubDate>Thu, 16 Apr 2020 15:52:45 +0800</pubDate><description><![CDATA[Lec 27 - kd Tree]]></description><category></category></item><item><title><![CDATA[CS61B - Lec 26 - Tries]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105531242</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105531242</guid><author>fourier_transformer</author><pubDate>Wed, 15 Apr 2020 19:33:57 +0800</pubDate><description><![CDATA[Lec 26 - TriesTriesImplementaion and Performance
这两天晚上都没睡好导致脑子木木的，昨天实现个HashMap实现了一晚上，还把resize的条件写成了&gt; loadFactor。。。顺便看了下HashMap的源码，好像还用到了红黑树，相当的复杂，好多东西我都没考虑到。
今天学习的是专门存储key为String, char类型的Map——Trie。...]]></description><category></category></item><item><title><![CDATA[CS61B - Lec 25 - Heaps, Priority Queue]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105509257</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105509257</guid><author>fourier_transformer</author><pubDate>Tue, 14 Apr 2020 14:19:14 +0800</pubDate><description><![CDATA[Lec 25 - Heaps, Priority QueueHeapsTree RepresentationsData Structures Summary
今天我们要实现的是这样的功能：

主要就是getSmallest和removeSmallest，keep track of the smallest item。这有什么用呢？
比如，接受了很多message输入，并且有一个对message和谐...]]></description><category></category></item><item><title><![CDATA[CS61B - Lec 24 - Hashing]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105485601</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105485601</guid><author>fourier_transformer</author><pubDate>Mon, 13 Apr 2020 14:43:40 +0800</pubDate><description><![CDATA[Lec 24 - HashingData Index ArraysEnglish String SetInteger Overflow and Hash CodesHash Tables: Handling CollisionsHash Table PerformanceHash Tables in JavaSummary
终于讲到了Hashing。早在leetcode第一题twoSum就见到了H...]]></description><category></category></item><item><title><![CDATA[CS61B - Tree Map - 二叉树遍历]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105474881</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105474881</guid><author>fourier_transformer</author><pubDate>Sun, 12 Apr 2020 20:07:18 +0800</pubDate><description><![CDATA[Tree Map
来自CS61B 19Spring的lab 7。Lab 7: TreeMap
要求以二叉树为核心数据结构，构造一个Map。也就是自己建一个nest class二叉树节点类。
put, get, containKey方法不用说，常见的二叉树递归。就说一下额外建的一个printInOrder()方法，按照key从大到小的顺序输出，有一种非常漂亮的递归实现方式。直接上代码。
/* Pri...]]></description><category></category></item><item><title><![CDATA[CS61B - Lec 23 - Red-Black Trees]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105466286</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105466286</guid><author>fourier_transformer</author><pubDate>Sun, 12 Apr 2020 12:17:04 +0800</pubDate><description><![CDATA[Lec 22 - Red-Black TreesTree RotationRed-Black Trees构造Red-Black Tree
这门课变得越来越抽象了。上课不带着实现结构了，只能课下去做lab咯。
上节课讲的B-Tree好是好，但是很难实现。这节课要讲的是同时兼顾BST的结构以及B-Tree的平衡特性的红黑树。
Tree Rotation
定义树的旋转操作。

将节点G向左旋转，意思就是...]]></description><category></category></item><item><title><![CDATA[CS61B - Lec 22 - B Tree]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105455651</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105455651</guid><author>fourier_transformer</author><pubDate>Sat, 11 Apr 2020 22:34:54 +0800</pubDate><description><![CDATA[Lec 22 - B TreeHeight, Depth and Performance2-3-4 and 2-3 Tree Operations(B-Trees)
上节课讲了二叉树，但是并没有讲二叉树是怎样建立的。如果不规定一种建立方式，那么有可能建出一个极高的二叉树，极限情况下会变成链表，失去了二叉树的意义。这节课主要为了优化这个问题，提出一种新的树形结构——B Tree。
Height, D...]]></description><category></category></item><item><title><![CDATA[CS61B - UnionFind & BubbleGrid]]></title><link>https://blog.youkuaiyun.com/fourier_transformer/article/details/105448708</link><guid>https://blog.youkuaiyun.com/fourier_transformer/article/details/105448708</guid><author>fourier_transformer</author><pubDate>Sat, 11 Apr 2020 11:25:59 +0800</pubDate><description><![CDATA[UnionFind（并查集）
sp19的lab6，18是没有的。要求是自己实现一遍UnionFind，然后做一个应用。
此处实现的是WeightUnionFind，按照树的weight决定连接优先级。在find方法里，包括了path compression。
public class UnionFind {

    private int[] parent;

    /** Creates a...]]></description><category></category></item></channel></rss>