udacity data analysis

Cluster analysis divides objects into clusters according to their differences, clusters are collections of data objects, and cluster analysis makes objects in the same cluster similar to objects in other clusters. Similarity and dissimilarity (dissimilarity) are evaluated based on the attribute values of the data objec

#-*-Coding:utf-8-*-# The Nineth chapter of Python for data analysis# Data aggregation and grouping operationsImport Pandas as PDImport NumPy as NPImport time# Group operation Process, Split-apply-combine# Split App MergeStart = Time.time ()Np.random.seed (10)# 1, GroupBy technology# 1.1, citationsDF = PD. DataFrame ({' Key1 ': [' A ', ' B ', ' A ', ' B ', ' a '],

the skewness coefficient is greater than 1 or less than 1 , called a highly skewed distribution, if the skewness coefficients are 0.5~1 or -1~0.5 is considered to be a medium-biased distribution; Peak State and its measurement ; the peak state is relative to the standard normal distribution. If a set of data obeys a standard normal distribution, then the value of the peak state coefficient is equal to 0, if the value of the peak state coefficient is

In recent years, the quantitative analysis of financial field has been paid more and more attention by theorists and practitioners, and the technology of quantitative analysis has made great progress, which has become a hot field of concern. The so-called financial quantification, is the combination of financial Analysis theory and computer programming technology

The content of this article is PHP serialize serialized data and JSON formatted data analysis. if you need it, refer to PHP serialize to serialize variables, return a string expression with variable types and structures, while JSON is a lighter and more friendly format for interface (AJAX, REST, etc.) data exchange. In

Recently encountered a fairly good, beginner-friendly project that describes how to parse JSON data and load it into a ListView.But personally, this tool can be used in all future implementations of similar functions.Projects can also use this architecture.This project is dealing with only one imgurl per news, and should be considered when the number of Imgurl is uncertain how to fix it.First, the project source code structure is as follows:Project DO

graphs, but the results can be further processed to obtain more detailed results. Each data also has an agent value, that is, the browser's user_agent information, through this information to know the operating system used,so the statistical results generated in the previous step can also be differentiated by operating system differences. Agent value: v. To distinguish a bar chart from an operating system (windows/non-Windows) Not all

After more than 10 years of development, China has made remarkable achievements in the construction and development of high-speed railway, and now has the world's largest and highest-speed high speed railway network. From the earliest 100 kilometers per hour "Dongfeng" diesel locomotives to the latest top speed of 486 kilometers of "harmony" high-speed car, China's railway technology to achieve a rapid leap-forward development, local technology has been in the forefront of the world.Similarly, i

Data Structure linked list _ single-chain table implementation and analysis, single-chain Data StructureSingle-chain table implementation and analysis The ListElmt struct represents a single element in the linked list (see example 1). This struct has two members: the data me

Examples of exception detection methods and ideas based on Big Data Analysis 1 OverviewWith the deepening of information technology in human society, the data produced by information systems is also growing exponentially. In-depth analysis of such data can produce a lot of v

=NewJsondata (); skill2["KeyCode"] ="W"; skill2["Name"] ="Crippled Blow"; skill2["Mp"] = +; skill2["CD"] =5; hero["Skills"]. ADD (SKILL2); Jsondata Skill3=NewJsondata (); skill3["KeyCode"] ="E"; skill3["Name"] ="Ruthless Iron hand"; skill3["Mp"] =Ten; skill3["CD"] =9; hero["Skills"]. ADD (SKILL3); Jsondata SKILL4=NewJsondata (); skill4["KeyCode"] ="R"; skill4["Name"] ="Norwalk Guillotine"; skill4["Mp"] = -; skill4["CD"] = -; hero["Skills"]. ADD (SKILL4); }JSON parsing voidLitpar

functions of read_csv and read_table are as follows:Read a text file by blockWhen working with very large files, or finding the set of parameters in a large file for subsequent processing, you only need to read a small part of the file or iterate over the file by block.Reading a few lines requires setting the nrows parameter, where the nrows subscript is starting from 0. So nrows=2 represents the first 3 lines. in [+]: result=pd.read_csv ('/home/zhf/1.csv ', nrows=2)in [+]: ResultOUT[20]:1 2 3