<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[ttinch的博客]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/ttinch</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; ttinch]]></copyright><item><title><![CDATA[数据结构总结]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102862759</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102862759</guid><author>ttinch</author><pubDate>Thu, 03 Jun 2021 17:08:32 +0800</pubDate><description><![CDATA[数据结构二叉树深度优先遍历（递归、非递归）前序遍历中序遍历后序遍历广度优先遍历（层序遍历）堆图最短路前k条最短路深度优先搜索（DFS）广度优先搜索（BFS）
二叉树
# Definition for a binary tree node.
class TreeNode:
    def __init__(self, x):
        self.val = x
        self.lef...]]></description><category></category></item><item><title><![CDATA[逻辑回归]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/106086848</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/106086848</guid><author>ttinch</author><pubDate>Tue, 12 May 2020 23:07:28 +0800</pubDate><description><![CDATA[逻辑回归1. 逻辑回归模型2. 损失函数3. 损失函数求解3.1 梯度下降法3.2 牛顿法4. 为什么sigmoid输出代表概率5. 共线性问题
1. 逻辑回归模型
逻辑回归将线性回归的预测值转换为0/1值，通常采用sigmoid函数g(z)=11+e−zg(z)=\frac{1}{1+e^{-z}}g(z)=1+e−z1​进行转换：
h(x)=11+e−(ωTx+b)h(x)=\frac{1}{1+e^{-(\omega^Tx+b)}}h(x)=1+e−(ωTx+b)1​
即
P(y=1∣x)=11+e−]]></description><category></category></item><item><title><![CDATA[线性回归]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/106034567</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/106034567</guid><author>ttinch</author><pubDate>Sun, 10 May 2020 22:21:33 +0800</pubDate><description><![CDATA[线性回归1. 线性回归模型2. 损失函数3. 损失函数求解3.1 最小二乘法3.2 梯度下降法
1. 线性回归模型
通过属性的线性组合进行预测。对于nnn维数据样本，有
f(x1,x2,⋯ ,xn)=ω0x0+ω1x1+⋯+ωnxn+bf(x_1,x_2,\cdots,x_n)=\omega_0x_0+\omega_1x_1+\cdots+\omega_nx_n+bf(x1​,x2​,⋯,xn​)=ω0​x0​+ω1​x1​+⋯+ωn​xn​+b
表示为矩阵形式
f(x)=ωTx+bf(x)=\omega^]]></description><category></category></item><item><title><![CDATA[广义线性模型（Generalized Linear Model）]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/106026978</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/106026978</guid><author>ttinch</author><pubDate>Sun, 10 May 2020 00:29:26 +0800</pubDate><description><![CDATA[广义线性模型广义线性模型（Generalized Linear Model）指数分布族广义线性模型建模（三个假设）线性回归推导Gaussian 分布的指数分布族形式广义线性模型进行建模逻辑回归推导Bernoulli分布的指数分布族形式广义线性模型进行建模Softmax回归（多分类）多项式分布的指数分布族形式广义线性模型进行建模
广义线性模型（Generalized Linear Model）
指数分布族
指数分布族具有如下形式
p(y∣η)=b(y)exp⁡(ηTT(y)−a(η)))p(y|\eta )=]]></description><category></category></item><item><title><![CDATA[【LeetCode】136/137/260. Single Number I/II/II 解题报告（Python）]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102680419</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102680419</guid><author>ttinch</author><pubDate>Mon, 09 Dec 2019 15:07:10 +0800</pubDate><description><![CDATA[【LeetCode】136/137/260. Single Number I/II/II 解题报告（Python）136. Single Number题目描述解法：对每个数做异或即为结果137. Single Number II题目描述解法：260. Single Number III题目描述解法：分组，位运算
136. Single Number
题目地址：https://leetcode.co...]]></description><category></category></item><item><title><![CDATA[机器学习之决策树]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102782472</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102782472</guid><author>ttinch</author><pubDate>Mon, 28 Oct 2019 20:28:04 +0800</pubDate><description><![CDATA[机器学习之决策树决策树原理生成过程停止条件优缺点划分选择信息增益（ID3）信息增益率（C4.5）基尼系数（CART）剪枝预剪枝后剪枝连续值与缺失值处理连续值处理缺失值处理回归树（CART）决策树参数其它
决策树原理
决策树是一种分类和回归的基本模型，可从三个角度来理解它，即：

一棵树
if-then规则的集合，该集合是决策树上的所有从根节点到叶节点的路径的集合
定义在特征空间与类空间上的条件概率...]]></description><category></category></item><item><title><![CDATA[存储基础（二）（6.29）]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/94020983</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/94020983</guid><author>ttinch</author><pubDate>Tue, 22 Oct 2019 10:10:25 +0800</pubDate><description><![CDATA[文章目录备份技术重复数据删除重复数据删除级别重复数据删除种类存储IO类型正确描述IO类型
备份技术
重复数据删除
重复数据删除级别
重复数据删除通过识别重复或冗余数据来降低存储需求。重复数据删除有多种级别，每个级别所对应的文件冗余识别能力有所不同：

文件级别重复数据删除：只要文件有任何修改，整个文件就被认为是一个新的文件，因而会被存储。只有在文件没有任何修改的情况下，该文件才被认为是个冗余文件，...]]></description><category></category></item><item><title><![CDATA[动态规划总结]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102671037</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102671037</guid><author>ttinch</author><pubDate>Tue, 22 Oct 2019 09:56:27 +0800</pubDate><description><![CDATA[动态规划总结带权间隔调度背包问题最长公共子序列 &amp; 最长公共子串最长公共子序列最长公共子串最长上升子序列
带权间隔调度

间隔调度：贪心算法，按照终止时间对任务进行排序


任务iii开始于sis_{i}si​，结束于fif_{i}fi​，拥有权重viv_{i}vi​，需要找出可完成的不冲突任务的最大权重。
定义一个函数P(i)P(i)P(i)，是指与任务i不重叠的索引最大值，该索引小于i...]]></description><category></category></item><item><title><![CDATA[【LeetCode】300. Longest Increasing Subsequence 解题报告（Python）]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102673387</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102673387</guid><author>ttinch</author><pubDate>Tue, 22 Oct 2019 09:55:52 +0800</pubDate><description><![CDATA[【LeetCode】300. Longest Increasing Subsequence 解题报告（Python）题目描述解法1：动态规划解法二：贪心算法+二分查找
题目地址：https://leetcode.com/problems/longest-increasing-subsequence/
题目描述
Given an unsorted array of integers, find th...]]></description><category></category></item><item><title><![CDATA[十大排序算法]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102661846</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102661846</guid><author>ttinch</author><pubDate>Mon, 21 Oct 2019 20:03:21 +0800</pubDate><description><![CDATA[十大排序算法冒泡排序选择排序插入排序归并排序快速排序一行代码实现常用快排实现算法导论版本，一层循环用栈实现非递归的快排程序希尔排序堆排序计数排序基数排序桶排序
参考：https://www.cnblogs.com/onepixel/p/7674659.html

冒泡排序

比较相邻的元素。如果第一个比第二个大，就交换它们两个；
对每一对相邻元素作同样的工作，从开始第一对到结尾的最后一对，这样在最...]]></description><category></category></item><item><title><![CDATA[【LeetCode】121. Best Time to Buy and Sell Stock 解题报告（Python）]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102605921</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102605921</guid><author>ttinch</author><pubDate>Thu, 17 Oct 2019 14:27:16 +0800</pubDate><description><![CDATA[【LeetCode】121. Best Time to Buy and Sell Stock 解题报告（Python）题目描述解法
题目地址：https://leetcode.com/problems/best-time-to-buy-and-sell-stock/
题目描述
Say you have an array for which the ith element is the price ...]]></description><category></category></item><item><title><![CDATA[【LeetCode】70. Climbing Stairs 解题报告（Python）]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102605153</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102605153</guid><author>ttinch</author><pubDate>Thu, 17 Oct 2019 13:49:50 +0800</pubDate><description><![CDATA[【LeetCode】70. Climbing Stairs 解题报告（Python）题目描述解法：动态规划
题目地址：https://leetcode.com/problems/climbing-stairs/submissions/
题目描述
You are climbing a stair case. It takes n steps to reach to the top.
Each tim...]]></description><category></category></item><item><title><![CDATA[【LeetCode】62. Unique Paths 解题报告（Python）]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102589387</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102589387</guid><author>ttinch</author><pubDate>Wed, 16 Oct 2019 20:59:37 +0800</pubDate><description><![CDATA[【LeetCode】62. Unique Paths 解题报告（Python）题目描述解法1：组合数直接求解防溢出（python大数不会溢出，给一个思路）类似动态规划，不可直接递归，有重复子问题解法2：动态规划
题目地址：https://leetcode.com/problems/unique-paths/
题目描述
A robot is located at the top-left corne...]]></description><category></category></item><item><title><![CDATA[【LeetCode】53. Maximum Subarray 解题报告（Python）]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102566778</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102566778</guid><author>ttinch</author><pubDate>Tue, 15 Oct 2019 17:31:20 +0800</pubDate><description><![CDATA[【LeetCode】53. Maximum Subarray 解题报告（Python）题目描述解法1：动态规划解法2：分治法分治法和动态规划区别
题目地址：https://leetcode.com/problems/maximum-subarray/
题目描述
Given an integer array nums, find the contiguous subarray (containing...]]></description><category></category></item><item><title><![CDATA[【LeetCode】14. Longest Common Prefix 解题报告（Python）]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102555132</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102555132</guid><author>ttinch</author><pubDate>Mon, 14 Oct 2019 21:25:39 +0800</pubDate><description><![CDATA[【LeetCode】14. Longest Common Prefix 解题报告（Python）题目描述解法1：排序，比较首位字符串解法2：暴力求解，按照长度最小的字符串遍历
题目地址：https://leetcode.com/problems/longest-common-prefix/
题目描述
Write a function to find the longest common prefi...]]></description><category></category></item><item><title><![CDATA[【LeetCode】4. Median of Two Sorted Arrays 解题报告（Python）]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102527780</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102527780</guid><author>ttinch</author><pubDate>Sat, 12 Oct 2019 22:12:08 +0800</pubDate><description><![CDATA[【LeetCode】4. Median of Two Sorted Arrays 解题报告（Python）题目描述解法：类二分查找
题目地址：https://leetcode.com/problems/median-of-two-sorted-arrays/
题目描述
There are two sorted arrays nums1 and nums2 of size m and n respe...]]></description><category></category></item><item><title><![CDATA[【LeetCode】2. Add Two Numbers 解题报告（Python）]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/102523986</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/102523986</guid><author>ttinch</author><pubDate>Sat, 12 Oct 2019 17:12:23 +0800</pubDate><description><![CDATA[【LeetCode】2. Add Two Numbers 解题报告（Python）题目描述解法一：先求和，再构建链表解法二：采用一个进位carry方便的完成一次遍历得出结果解法三：递归
题目地址：https://leetcode.com/problems/add-two-numbers/
题目描述
You are given two non-empty linked lists represent...]]></description><category></category></item><item><title><![CDATA[pyecharts 无法找到bootstrap/base.html]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/99415034</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/99415034</guid><author>ttinch</author><pubDate>Tue, 13 Aug 2019 11:38:31 +0800</pubDate><description><![CDATA[pyecharts1.3.1采用jinja2 Markup渲染网页，
return Markup(chart.render_embed(template_name='index.html'))

{% extends "bootstrap/base.html" %}

提示
jinja2.exceptions.TemplateNotFound: bootstrap/base.html

调用路径：...]]></description><category></category></item><item><title><![CDATA[存储基础（一）（6.28）]]></title><link>https://blog.youkuaiyun.com/ttinch/article/details/93967120</link><guid>https://blog.youkuaiyun.com/ttinch/article/details/93967120</guid><author>ttinch</author><pubDate>Fri, 28 Jun 2019 17:47:06 +0800</pubDate><description><![CDATA[文章目录基础概念DAS、NAS、SANSCSI访问控制原理SCSI-2 Reserve(预留)/Release(释放)/Reset（重置）SCSI-3 Persistent Reserve (PR)/ PREEMPT（抢占）
基础概念

lun：Logical Unit Number，也就是逻辑单元号，其主要作用是为了给相连的服务器分配逻辑单元号(LUN)。磁盘阵列上的硬盘组成RAID组后，通常连...]]></description><category></category></item></channel></rss>