introduction to computation and programming using python pdf

data property, and a function is used to represent a method property.In real life, there are objects after the first class, such as the first people, after the concept of human, and in programming, is the first class, after the object, class generation object.declare a class: similar to the definition of a functionDefining functions: Using the DEF keyword1 def functionname (args): 2 ' function documen

performance to the greatest extent possible, using a lower-level, low-productivity language like C + + is worth it.Python is not an ideal programming language for highly concurrent, multi-threaded applications, because Python has a thing called the GIL (Global Interpreter Lock), which is a mechanism that prevents the interpreter from executing multiple

I. Introduction of Tkinter Tkinter is a Python module, an interface called TCL/TK, which is a cross-platform scripting GUI interface. Tkinter is not the only Python graphics programming interface, but it is one of the more popular ones. The biggest feature is the cross-platform, the disadvantage is the performance is

This article mainly introduces the Getting Started Tutorial on network programming using threads in Python. This article is from the technical documentation on the IBM official website. For more information, see Introduction For Python, there is no lack of concurrency optio

in a previous article on the greedy algorithm to solve the problem of active selection ("Introduction to the algorithm" Greedy algorithm activity selection problem ), found that there is a practice 16.1-1 is to use dynamic programming to solve the problem of active selection. In fact, the matrix chain is similar to the previous multiplication, but also consider the partition of the activity is which, and tw

about PythonPython is a high-level scripting language that combines explanatory, compiled, interactive, and object-oriented.Python's design is highly readable, with English keywords often used in other languages, some punctuation in other languages, and it has a more distinctive grammatical structure than other languages. Python is an interpreted language: This means that there is no compilation in the development process. Similar to the PHP

server. close () Client code: #! /Usr/bin/env python #-*-coding: UTF-8-*-import socket # create client socket object clientsocket = socket. socket (socket. AF_INET, socket. SOCK_STREAM) # server IP address and port number tuples server_address = ('2017. 0.0.1 ', 8888) # The IP address and port number specified for client connection. connect (server_address) while True: # input data = raw_input ('Please input: ') # client sends data to clientsocket. s

=FalseGlobalSecret_number Secret_number= Random.randint (0,999) Globalnumber_of_guess number_of_guess= 10Print "New game. Range is [0,1000]" Print "Number of remaining guesses is", Number_of_guessPrint definput_guess (guess):#main game logic goes here GlobalGuess_number Guess_number=Int (guess)Print "Guess was", Guess_numberGlobalnumber_of_guess number_of_guess-= 1Print "Number of remaining guesses is", Number_of_guessifSecret_number >Guess_number:Print "higher!" Print

1 #题目: If a number is exactly equal to the sum of its factors, this number is called the "end number". For example, 6=1+2+3. Programming to find all the finished numbers within 1000.Code:2 3 for I in Range (1,1001): 4 s = 0 5 for j in Range (1,i): 6 if I%j = = 0:7 S + = J 8 if s = = I:9 print (i)Operation Result:[[email protected] code_100]# python code_19.py 628496[[email protected] code_100]#Code Explanat

address families, Python supports a variety of address families, but since we only care about network programming, most of the time I use af_inet only)Iv. Socket WorkflowA scene in the life. You have to call a friend, dial first, a friend hears a phone call, and then you and your friend establish a connection, you can talk. When the communication is over, hang up the phone and end the conversation. The sce

The system. threading namespace provides classes and interfaces that enable multi-threaded programming. There are three methods for creating threads: thread, threadpool, and timer. Next I will give a brief introduction to their usage methods one by one.1. threadThis may be the most complicated method, but it provides various flexible control over the thread. First, you must use its constructor to create a t

Hadoop is an open-source distributed parallel programming framework that implements the MapReduce computing model. with Hadoop, programmers can easily write distributed parallel programs and run them on computer clusters, complete the calculation of massive data. Introduction to MapReduce and HDFS What is Hadoop? Google proposed the programming model MapReduce a

non-zero value ). This restriction is achieved by using the appropriate if statement and continue statement. As described in the previous article, the continue statement starts the next iteration of the loop containing it. Another way to achieve the same result is to test whether the current item in tuple is an even number (if not num % 2 :). If it is true, add the current item to the total running number. Once the code completes the iteration in tup

1 #题目: A ball from the height of 100 meters free fall, each landing after the back to the original height of half, and then fall, the 10th time to landing, how many meters? How high is the 10th time rebound?Code:2 3 h = 0 4 li = [] 5 for I in Range (1,11): 6 s = 100/(2** (i-1)) 7 li.append (s) 8 9 for x in Li:10 H + = x print (LI) print (' The ball is on the tenth time, it has been%.10f m, the 10th bounce height is%.10f '% ((h*2-100), LI[-1]/2)Operation Result:[[email protected] code_100]#

1 #题目: Two table tennis team to play, each out of three people. Team A for A,b,c three, team B for X, Y, z three people. Have drawn lots to determine the contest list. Someone asked the team for a list of matches. A says he does not compare with X, C says he does not compare with x,z, please compile the procedure to find out the list of the three teams.Code:2 3 ' a '! = ' x ' 4 ' c '! = ' x ' 5 ' c '! = ' Z ' 6 7 if (' x '! = ' A ') and (' x '! = ' C '): 8 print (' x---B ') 9 if ' C '! = ' Z ':

(stop_num)#define event handlers for buttons; "Start", "Stop", "Reset"defStart_handler (): Timer.start ()defStop_handler (): Timer.stop ()defReset_handler (): Timer.stop ()GlobalTGlobalt_str Reset_score ()#Define event handler for timer with 0.1 sec intervaldefTimer_handler ():GlobalTGlobalT_str T= t + 1T_str=format (t)defTimer_score_handler (): Update_score ()#Define Draw HandlerdefDraw_handler (Canvas): Canvas.draw_text (t_str, Position,36," White") Canvas.draw_text (SCORE_STR, [160, 20], 16,

() Close the socket. S.getpeername () Returns the remote address of the connection socket. The return value is typically a tuple (ipaddr,port). S.getsockname () Returns the socket's own address. Typically a tuple (ipaddr,port) S.setsockopt (Level,optname,value) Sets the value of the given socket option. S.getsockopt (Level,optname[.buflen]) Returns the value of the socket option. S.settimeout (Timeout

Introduction to MVC Programming using Agavi, part 2nd: Adding Forms and database support using Agavi and Doctrine 2 Get Database records Now that communication between Agavi, doctrine and MySQL is clear, you need to write a viewaction to get and display the list of cars from the MySQL database. First, populate the li

+ high)/2.0CTR + =1 assertCtr -,' iteration count exceeded ' Print ' Bi method. Num. Iterations: ', CTR,' Estimate: ', GuessreturnGuess def squarerootnr(x, epsilon): "" " Return y s.t. Y*y is within epsilon of X" " assertEpsilon >0,' Epsilon must is postive, not '+ str (epsilon) x = float (x) guess = x/2.0Guess =0.001diff = Guess * *2-X ctr =1 whileABS (diff) > Epsilon andCtr -:# print ' Error: ', diff, ' Guess: ', guess guess = guess-diff/(2.0*guess)diff = Guess * *2-X ctr +

(waiting for the data is ready)----The kernel waits for a readable(2) Copy the data from the kernel into the process (Copying the data from the kernel to the process)----Copy the kernel readIt is important to remember these two points because the difference between these IO model is that there are different situations in both phases.1.3What are I/O operations? network Operation , that is, the establishment of the socket object, to establish a connection, send, receive, processing reque