python data analysis coursera

1.1. Foreword This way we use the memory analysis framework pandas to analyze the daily PV.1.2. Praise to Pandas In fact, personal to pandas this module is quite favorable. I use pandas to complete many of the day-to-day practical gadgets, such as the production of Excel reports, simple data migration, and so on. To me, pandas is a memory MySQL, I usually call him the program SQL. 1.3. Pandas

the string object method Split () method splits the string:The Strip () method removes whitespace and line breaks:Split () in combination with strip () using:The "+" symbol allows you to concatenate multiple strings together:The join () method is also the connection string, comparing it to the "+" symbol:The In keyword determines whether a string is contained in another string:The index () method and the Find () method determine the location of a substring: the difference between the index ()

;deff (x, y): -...return10*x+y + ... ->>> B = Np.fromfunction (f, (5,4), dtype=int) +>>>b AArray ([[[0, 1, 2, 3], at[10, 11, 12, 13], -[20, 21, 22, 23], -[30, 31, 32, 33], -[40, 41, 42, 43]]) ->>> b[2,3] -23 in>>> B[0:5, 1]#second column -Array ([1, 11, 21, 31, 41]) to>>> b[:, 1]#second column +Array ([1, 11, 21, 31, 41]) ->>> B[1:3,:]#second row, third row theArray ([[[10, 11, 12, 13], *[20, 21, 22, 23]]) $GT;GT;B[-1]#equivalent to B[-1,:], last linePanax NotoginsengArray ([40, 41, 42, 43])

After installing the NumPy module, I started to do a few small tests to run, but when I created numpy.py this filenumpy.pyimport numpyy = Numpy.array ([[[11,4,2],[2,6,1],[32,6,42]])print(y)After the operation error:Traceback (most recent):File "D:\Python_Reptile\numpy.py", line 1, Import NumPyFile "D:\Python_Reptile\numpy.py", line 2, y = Numpy.array ([[11,4,2],[2,6,1],[32,6,42]])Attributeerror:module ' NumPy ' has no attribute ' array 'Baidu opened the query for a long time, and the previous te

)#Display OutputFigure () Gray () forIinchRange (File_len): Subplot (3,4,i + 1) pic= Immatrix[i].reshape (180,360) pic= Pic[::-1]#picshow = rot90 (pic,4)imshow (pic) Colorbar () show ()#Convert to sample populationX =Immatrix. T#get to this sizeM,n = X.shape[0:2]#obtain the average of each sampleMeanval = mean (X,axis =0)#Tempmean = Tile (Meanval, (64800,1))#Sample matrix de -CentralizedX = X-tile (Meanval, (64800,1))#Calculate covarianceS = dot (x.t,x)/(m-1)#calculate eigenvalues eg and eigenve

has a mechanism called the Global Interpreter Lock, GIL, which prevents the interpreter from executing multiple Python byte-code directives at the same time. PS. Cython projects can integrate OpenMP (c framework for parallel computing) NumPy (numerical Python) Scientific Computing base package, function: Multidimensional array objects ndarray the array of elements to perform the element-level calculation

First, Brief introduction matplotlib1. Matplotlib is a powerful toolkit for Python drawing and data visualization2. Installation method: Pip Install Matplotlib3. Citation method: Import Matplotlib.pyplot as Plt4. Drawing function: Plt.plot ()5. Display Image: Plt.show () --Linetype LineStyle (-,-.,--,.. ) -colour color (b,g,r,y,k,w,... 2, plot function draw multiple curves 3, Pandas package

C, C + +, FORTRAN code integration into Python tools Pandas: A large number of data structures and functions that handle structured data Precise indexing, reshaping, slicing, chopping, aggregating, selecting subsets High performance time series features and tools Matplotlib: The most popular library for plotting

ordered data such as time series, it may be necessary to do some interpolation when re-indexing, the method option can achieve this purpose:For ordered data such as time series, it may be necessary to do some interpolation when re-indexing, the method option can achieve this purpose: Method Parameter Introduction Parameters Description Ff

Before doing data analysis, many are using Oracle or MySQL, SQL to complete the query and statistical data analysis, but with the increase in data volume, the database with the development of a NoSQL database, due to the changes in the database and its underlying technology

DataFrame.hist(Data,Column=none,By=none,grid=true,Xlabelsize=none,Xrot=none,Ylabelsize=none,Yrot=none,Ax=none,Sharex=false,Sharey=false,Figsize=none,Layout=none,bins=10,**kwds)Data : DataFramecolumn : string or sequence strings or sequences by: object, optional If passed, then used to form histograms (histogram) for separate groups Grid : Boolean, default True grid line, defaul

Date-time data types and tools from Import = datetime.now ()print(now.year,now.month,now.day)# stores time in milliseconds Delta = now-datetime (1992,2,2)print(delta)print(delta.days) # You can subtraction from import timedeltaprinton the timestamp ( Delta+timedelta (12))String and DateTime conversions#Time Turn strTime_str = Now.strftime ('%y-%m-%d')Print(TIME_STR)#Str Turn TimeTIME_STR2 = Datetime.strptime (Time_str,'%y-%m-%d')Print(TIME_STR2)#wo

NumPy:NdarrayPandas:DataFrameMatplotlib:SciPy:IntegrateLinalgOptimizeSignalSparseSpecialStatsWeaveCanopy InstallationPython variable typeNumbers (digital)--int,long,float,complexString (String)-counting starting at 0, starting bit, ending (excluding end)List (lists)--can be changed, assignedTuple (tuple)--Non-changing assignmentDictionary (dictionary)--can be changed, assigned valuePython Data type conversionsPython operator--arithmetic operator, comp

Size of rental room (area)　　　　　　　　　 Rental Rate (price) Compare informationCode1 ImportMatplotlib as Mpl2 ImportMatplotlib.pyplot as Plt3 ImportPandas as Pad4 ImportSeaborn as SNS5 ImportNumPy as NP6 7Sns.set_style ('Dark')8KF = Pad.read_csv ('Kf.csv')9 Ten defSinplotone (): OneFig,ax =plt.subplots () AAx.violinplot (kf[' Price']) - plt.show () - the defsinplottwo (): -Sns.set_style ('Whitegrid') -Sns.boxplot (kf[' Price'],palette=' Deep') - #sns.despine (left=true) + plt.show (

Getting started with Python for data analysis--pandas Based on the NumPy established from pandas importSeries,DataFrame,import pandas as pd One or two kinds of data structure 1. Series A python-like dictionary with indexes and values

The way of thinking is mainly based on this article, linking:Http://www.jb51.net/article/78667.htmBut when the installation of brew, it may be the problem of the site, has been an errorSo looking for information from the Internet, brew installation needs a new window, non-root developmentSpecific methods refer to connection: http://jingyan.baidu.com/article/335530da8b2b0419cb41c338.htmlThe command line is as follows: Ruby-e "$ (curl-fssl https://raw.githubusercontent.com/Homebrew/install/m

Vectorization refers to using an array expression instead of a loop to manipulate each element in the array.The general functions provided by NumPy (both Ufunc functions) are functions that perform element-level operations on data in Ndarray. For example, the square function computes the square of each element, and the rint function rounds each element:There are also some functions that accept 2 parameters, called two ufunc, such as the Add function a