python for data analysis 2nd edition

I. Related NumPy(i) Official explanationsNumPy is the fundamental package for scientific computing with Python. It contains among other things: A powerful N-dimensional Array object Sophisticated (broadcasting) functions Tools for integrating C + + and Fortran code Useful linear algebra, Fourier transform, and random number capabilities Besides its obvious scientific uses, NumPy can also is used as an efficient multi-dimensio

]])Mathematical and statistical methods:NumPy also provides a number of statistical functions to perform statistical operations on data, such as averaging, variance, and so on. Refer to the following table for detailsin [+]: arrOUT[35]:Array ([[0, 1, 2, 3, 4],[5, 6, 7, 8, 9],[10, 11, 12, 13, 14]])In [approx]: Np.mean (arr)OUT[36]: 7.0In [PNS]: np.std (arr)OUT[37]: 4.3204937989385739In []: Np.var (arr)OUT[38]: 18.666666666666668With these methods, we c

, indicating that age was related to survival.3.2.4 the relationship between brothers and sisters and whether they are alive or notFrom the data, siblings have the highest survival rate in 1-2.3.2.5 whether there is a relationship between parents ' children and survivalThe data show that the number of parents and children in 1-3 survival rate is the highest, the more the number is decreased survival rate.Th

3A3 6 6 6A4 9 9 9Six sorts and rankingsTo sort a row or column index, you can use the sort_index method, which returns a sorted new objectIn [133]: FrameOUT[133]:E C DA3 0 1 2A2 3 4 5A0 6 7 8A1 9 10 11Sort the row indexIn [134]: Frame.sort_index ()OUT[134]:E C DA0 6 7 8A1 9 10 11A2 3 4 5A3 0 1 2To sort a column indexIn [135]: Frame.sort_index (Axis=1)OUT[135]:C d EA3 1 2 0A2 4 5 3A0 7 8 6A1 10 11 9If you want to sort the data for a particular column,

mature frame or wheel that can meet my needs? (Multi-threading, and can run at 7x24 hours, because the number of acquisitions is huge) In addition to ask, how to store the collected content (million to tens of millions), the data there are some digital data, the need for statistical analysis, with MySQL can it? Or is there any other more mature and simple wheels

Python data structures and algorithms-algorithm analysisAn interesting problem often occurs, that is, two seemingly different programs. Which one is better? To answer this question, we must know that the program differs greatly from the algorithm representing the program. the algorithm is a general command that solves the problem. provides a solution to any instance problem with specified input, and the alg

Using Python for data analysis (5) NumPy basics: ndarray index and slicing,Concept understanding IndexYou can use an unsigned integer to obtain the values in the array.SliceThat is, the description of a segment in a logarithm group. One-dimensional array Index of one-dimensional arrayThe indexing of one-dimensional arrays is similar to that of

[Python Data Analysis] Python3 multi-thread concurrent web crawler-taking Douban library Top250 as an example, python3top250 Based on the work of the last two articles [Python Data Analysis] Python3 Excel operation-Take Douban lib

Most of the students who Do data analysis start with excel, and Excel is the most highly rated tool in the Microsoft Office Series.But when the amount of data is very large, Excel is powerless, python Third-party package pandas greatly extend the functionality of excel, the entry takes a little time, but really is the

Use Python for data analysis _ Numpy _ basics _ 2, _ numpy_2Numpy data types include: Int8, uint8, int16, uint16, int32, uint32, int64, uint64, float16, float32, float64, float128, complex64, complex128, complex256, bool, object, string _, unicode _Astype Display Methods for converting array types For example:

# #之前已经有很多人写过相关内容, but I have not read before, this crawler is also in accordance with their own ideas written, may be more ugly, please forgive me!I as a novice Python crawler and stock market leek, because of time every night no way to turn billboard data, so I hope to use the Crawler to filter out useful information for my analysis (in fact, I want to lazy ...

Data volume: 3,289,329 people.Data acquisition tool: Distributed Python crawlerAnalysis tool: ElasticSearch + KibanaAnalysis angle: geographical location, gender ratio, all kinds of rankings, universities, active level.Please note:All of the following analysis results are based on the personal information of the 3 million users I crawl, non-authoritative

first, the initial knowledge of pandas Pandas is a very useful library based on NumPy, which has two unique basic data Structures series (one-dimensional) and dataframe (two-dimensional) that make data operations simpler. Although pandas has two data structures, it is still a library of Python, so some

The Pandas object has some common mathematical and statistical methods. For example, the sum () method, which makes the column subtotal: the sum () method passed in Axis=1 is specified as a horizontal summary, which is subtotal: Idxmax () gets the index of the maximum value: There is also a rollup that is cumulative, cumsum (), compared to it and Su The difference between M ():The unique () method is used to return only values in the data: the Value_

[Python Data Analysis] solve and optimize some problems in Python3 Excel (2), pythonpython3 After the previous article titled "Python Data Analysis" and "Excel in Python3"-taking Douban book Top250 as an example to crawl the top P

, time data. And there are calendar features. The datetime, time, and calendar modules are used primarily. #-*-coding:utf-8-*-ImportNumPy as NPImportPandas as PDImportMatplotlib.pyplot as PltImportdatetime as DT fromDatetimeImportDatetimenow=DateTime.Now ()#datetime stores time in millisecondsPrintNow,now.year,now.month,now.day,now.microsecond,'\ n'#print datetime (2015,12,17,20,00,01,555555) #设置一个时间#Datetime.timedelta represents a time difference bet