题目大意:有一个数列,将其分成m段,求最小方差 先弄出n^3的dp,打出决策点,然后发现决策点是单调递增的,决策单调性搞一搞就可以了 #include<bits/stdc++.h> #define ll long long #define maxn 3010 using namespace std; int n,m; int a[maxn],sum[maxn]; double f[maxn][maxn],x; double sqr(double x){return x*x;} void sol
计算熵的函数: # -*- coding: utf-8 -*- import math #the function to calculate entropy, you should use the probabilities as the parameters def entropy(*c): result=-1; if(len(c)>0): result=0; for x in c: result+=(-x)*math.log(x,2) return result; if (__name__=
Shannon entropy is one of the most important metrics in information theory. Entropy measures the uncertainty associated with a random variable, i.e. the expected value of the information in the message (in classical informatics it is measured in bits
From: johndcook.com/blog For a set of positive probabilities pi summing to 1, their entropy is defined as (For this post, log will mean log base 2, not natural log.) This post looks at a couple questions about computing entropy. First, are there any
题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=1053 Entropy Description An entropy encoder is a data encoding method that achieves lossless data compression by encoding a message with “wasted” or “extra” information removed. In other words, entropy e
熵的概念在统计学习与机器学习中真是很重要,熵的介绍在这里:信息熵 Information Theory .今天的主题是最大熵模型(Maximum Entropy Model,以下简称MaxEnt),MaxEnt 是概率模型学习中一个准则,其思想为:在学习概率模型时,所有可能的模型中熵最大的模型是最好的模型:若概率模型需要满足一些约束,则最大熵原理就是在满足已知约束的条件集合中选择熵最大模型.最大熵原理指出,对一个随机事件的概率分布进行预测时,预测应当满足全部已知的约束,而对未知的情况不要做任何主
Information Entropy Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemCode=3827 Description Information Theory is one of the most popular courses in Marjar University. In this course, there is an impo
I - Information Entropy Time Limit:2000MS Memory Limit:65536KB 64bit IO Format:%lld & %llu Submit Status Description Information Theory is one of the most popular courses in Marjar University. In this course, there is an important chapter abo
题目链接:http://poj.org/problem?id=1521 Entropy Time Limit: 1000MS Memory Limit: 10000K Description An entropy encoder is a data encoding method that achieves lossless data compression by encoding a message with "wasted" or "extra" info
Information Entropy Time Limit: 2 Seconds Memory Limit: 131072 KB Special Judge Information Theory is one of the most popular courses in Marjar University. In this course, there is an important chapter about information entropy. Entropy is
Entropy Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 373 Accepted Submission(s): 208 Problem Description An entropy encoder is a data encoding method that achieves lossless data compression b