Python

One, the creation and transformation of tuples:Ages = (one, 22, 33, 44, 55) Ages = Tuple (11ages = tuple ([]) # string, list, dictionary (default is key) Tuples can basically be viewed as non-modifiable lists Tuple (iterable),

First, create a dictionary:D = { "name": "Morra", #字典是无序的 "age": " Gender": ' m '}a = Dict () b = Dict (k1=123,k2= "Morra")Second, dictionary commonly used: modify or add a dictionary:Other common methods: Len (a)

1. IteratorsIterators are a way to access the elements of a collection. The iterator object is accessed from the first element of the collection until all of the elements have been accessed and finished. Iterators can only move forward without going

Re. Sub (pattern, repl, string, count=0, flags=0)Re.sub meaning, function, function is:For the input string, use the regular expression (the powerful string processing function) to implement (relatively complex) string substitution processing, and

1 Import OS 2 ' f:/save_file/seminarseries/ ' 3 for inch Os.walk (path): 4 Print (Root)This prints out two paths that represent the path currently being traversed , the first is the path to the current directory folder, and the other is the

How to perform cross-browser testingIf we use Selenium webdriver, we can automatically run test cases on different browsers such as IE, Firefox, Chrome, and so on.To be able to execute test cases simultaneously on different browsers on the same

Topic:Use Python to generate a 4x4 two-dimensional array and rotate it clockwise by 90°The source code is as follows:Import randomdatarow=[]data=[]for i in range (4):     for j in  range (4):         datarow.append (Random.randint (10,80))      data.

Let's start by identifying the requirements:Write a registered program, enter USERNAME,PASSWD,CONFIRMPASSWDAfter successful registration, the prompt registration is successful, the program exits, requiring the user name cannot be repeatedThe number

TextWrap formatting text by adjusting the position of line breaks__all__ = ['textwrapper'wrap'Fill 'dedent' 'indent ' Shorten ']Fill () Adjust line breaks, each line shows the given width""" Asdsafsdkafsadfsadfasdsadfasdfsad """ Print (text) Print (

Sys.argv[] is used to get command line arguments, Sys.argv[0] represents the code itself file path, so the parameters starting from 1, the following two examples illustrate:1. A simple example of using sys.argv[]:The following is the sample1.py file:

What if you want to use Python for multiple inputs like the ACM topic? Because in Python I now only find the input function to enter, only the input string, but input has a function to remove the space, so you can use the method of processing the

modelform    a.  class meta:             model,                            #  corresponding to model             fields=None,                      #  Fields             exclude=None,                     #  Exclude Fields             labels=None,     

In Python, there are also global variables and local variables, but as far as I know, if a variable defined in the if is a global variable that falls down, there is also a function definition and return in Python, usually defining a function:def

Use native Python developed Web server, entry level!#!/usr/bin/python#-*-coding:utf-8-*-ImportOs#The OS module in the Python standard library contains common operating system featuresImportRe#Introducing Regular Expression ObjectsImportUrllib#used

Create a two-way queueImport COLLECTIONSD = Collections.deque ()Append (add an element to the right)Import COLLECTIONSD = Collections.deque () d.append (1) d.append (2) print (d) #输出: Deque ([1, 2])Appendleft (add an element to the left)Import

Python uses sys.argv[] to implement external parameters from the programSYS.ARGV returns a tuple, the first element of the tuple is the program itself, and the second element is followed by each parameter that we specify by entering. That is, the

Li = [33, 2, 10, 1,564,880,8,99,51,3]# for I in range (Len (LI)-1):# current = Li[i]# next_value = li[i + 1]# if li[i] > li[i + 1]:# temp = Li[i]# Li[i] = li[i + 1]# Li[i + 1] = Temp# Print (LI)## for I in range (Len (LI)-2):# if li[i] > li[i + 1]:#

In the previous chapter, we learned some basic methods of Python multi-process programming: Using the process, Pool, Queue, Lock, pipe, and other classes provided by the cross-platform multi-process module multiprocessing, to achieve child process

Ubuntu16.04 sets python3 as the default value, and ubuntu16.04python3 Ubuntu uses Python 2.7 By default, so the Python package is installed with Python 2.   Use alternativesMechanism Change py3 to default. Execute in shell: sudo update-alternatives -

Python small topic exercises, python --- Job 1: With the * dictionary * output directory, you can select a directory to enter. You can roll back and exit! # Conding: utf8Menu = {'beijing': {'changping ': {'shahe': {'changping maternal and