python chart library

occupy different storage spaces), while Chinese characters convert 1 Unicode characters into 3 UTF-8 characters, and you see \xe4 is one of the bytes, because its value is 228 , no corresponding letter can be displayed, so the numeric value of the byte is displayed in hexadecimal. len () function can return the length of a string: >>> len (U ' abc ') 3>>> len (' abc ') 3>>> len (U ' Chinese ') 2>> > Len (' \xe4\xb8\xad\xe6\x96\x87 ') 6 in turn, the UTF-8 code represents the string ' xxx '

A total of 6 kinds of library recommended, strongly recommend requests library. One of the Web libraries: Httplib Library #!/usr/bin/env python #coding =utf8 import httplib httpclient = None try: httpclient = Httplib. Httpconnection (' www.baidu.com ', timeout=30) httpclient.request (' Get ', '/') #res

we're talking about using the commands module to execute Linux shell commands, and when we write operations scripts in Python, we often need to execute the Linux shell commands, and the commands module in Python is dedicated to calling Linux Shell command, and return the status and results, here are the 3 main functions of the commands module:1.commands.getoutput (' Shell command ')2.commands.getstatus (' f

The default terminal launcher Python in Python is in the/usr/bin/directory. The default system library path in Python is in the/usr/lib/pythonx.x/directory. The default Third-party library path in Python is in the/usr/local/lib/

Python third-party library generation 17th-multiprocessing Library Speaking of concurrency, we think of multithreading and multi-process. So is multi-process or multi-thread used? This depends on the situation. Our programs are generally divided: 1) network-consuming (most of the time is in network interaction ); 2) CPU consumption (Make full use of multiple core

/********************************************************************* * Author:samson * date:02/02/2015 * Test PL Atform: * 3.13.0-24-generic * GNU bash, 4.3.11 (1)-release * *********************************** ********************************/In the HelloWorld project, a simple two-sum program was compiled, and after compiling it into a shared library, how would you use Python to invoke it?use the LL comm

Use of itertools library in Python standard library, pythonitertools Preface Because there have not been many things recently, I want to write some technical articles to share with you, and also sort out the knowledge that I have accepted for a while, this is the truth. Many people are committed to writing Python code

Excerpt from: http://blog.chinaunix.net/uid-16360955-id-3351990.html for retained learning1. Common built-in functions: (can be used directly without import)Help (obj) online, obj is any typeCallable (obj) to see if an obj can be called like a functionRepr (obj) obtains a representation string of obj that can be used to reconstruct a copy of the object using the string evalEval_r (str) represents a valid Python expression that returns the expressionDi

10 of python third-party Library Series-commands LibraryWe are talking about using the commands module to execute Linux shell commands. When we use Python to write O M scripts, we often need to execute linux shell commands, the commands module in Python is used to call the Linux shell Command and return the status and

Simple application of Pymongo library The Pymongo library is a library of Python operations MongoDB. The following is a brief introduction to the simple use of Pymongo. Create MONGO client Select database and set merge insert Data Import Pymongo client = Pymongo. Mongoclient (host,port) #client = Pymongo. Mongoclient

The requests Library is a good HTTP library for Python, and it can be very simple to perform various operations of HTTP, such as GET, post, and so on. However, the network request that the library executes is synchronous, that is, after the CPU sends the request instruction, the IO performs the operation such as send a

Common Standard Library Standard library DescriptionBuiltins built-in function default loadOS Operating System interfaceSYS Python's own operating environmentCommon Tools for FunctoolsJSON encodes and decodes JSON objectsLogging Logging, debuggingMultiprocessing Multi-processThreading MultithreadingCopy copyTimeDateTime Date and TimeCalendar calendarsHashlib Encryption algorithmRandom generating random num

We're talking about using the commands module to execute Linux shell commands, and when we write operations scripts in Python, we often need to execute the commands of the Linux shell, and the commands module in Python is dedicated to invoking the Linux shell commands. and return the status and results, here are the 3 main functions of the commands module:1.commands.getoutput (' Shell command ')2.commands.g

'%%xxx%% '" Print sql_str# select * from book where name like '%xxx% 'If this is the case, the printed SQL statement can be run under the SQL command line, but the following error is reported in my Django:' Cursor ' object has no attribute ' _last_executed 'I found on the internet for a long time, all said as long as the "percent" on the line, my is an error. So I boldly added "%%%%", tell the compiler I this is a percent semicolon, incredibly ok!4. Sum up, in Django if Add 2 "%" also reported

Simulate logon using the Request library in Python (1): The font library (no encryption, no verification code), pythonrequest Such simple (Insecure) login forms are rare. The following figure shows the log-on Form of the font library, saving irrelevant content: 1 Through packet capture analysis, we can find that the u

Transferred from: http://blog.csdn.net/jurbo/article/details/52334345Write this cause is, or because in the Python challenge, sometimes want to solve problems, even should use which class library do not know, but also to Baidu (I do not believe that I am a person so embarrassed TVT)It seems that since I learned the basics of Python syntax, I've seen some of the c

recent work has not made any progress, I can only say ExtJS a little bit big, hard to chew ~ In Python, it is often possible to move from one object to another to facilitate subsequent computations, which can be implemented using copies. Generally speaking, the copy is divided into three kinds: 1. pointer reference, 2. Shallow copy, 3. Deep copy. One, pointer reference Objects in Python are assigned

) ->>>RA +[0, 2, 3, 9, 7, 8, 5, 6, 1, 4] A>>> Sample (ra,4) at[1, 8, 5, 9]3. Random seeds1>>> Seed (10)2>>>random ()30.57140259468991354>>>random ()50.42888905467511466>>>random ()70.57809130113447048>>> seed (1)9>>>random ()Ten0.13436424411240122 One>>>random () A0.8474337369372327 ->>> Seed (10) ->>>random () the0.5714025946899135 ->>>random () -0.4288890546751146 ->>>random () +0.5780913011344704It can be seen that pseudo-random numbers are generated by random seeds.4. Monte Carlo (Monte Carl

Use the PDB library debugging program in Python and the pythonpdb library debugging The pdb library that comes with Python finds that it is very convenient to use pdb to debug the program. Of course, pdb cannot be used for remote debugging or multithreading. There are multip

Example: Draw a Python#Turtle: Drawing Library (Turtle Library)ImportTurtleturtle.setup (650,350,200,200) Turtle.penup () turtle.fd (-250) Turtle.pendown () turtle.pensize (25) Turtle.pencolor ("Purple") Turtle.seth (-40) forIinchRange (4): Turtle.circle (40,80) turtle.circle (-40,80) turtle.circle (40,80/2) TURTLE.FD (40) turtle.circle (16,180) TURTLE.FD (40*2/3