learn python 3 hard way review

notation reserved 2 decimal places>> 1.29e+00Formatting operator Auxiliary directivesSymbolic effect* Define width or decimal point accuracy-Used for left alignment+ Show plus sign (+) in front of positive number# 0 (' 0 ') is displayed in front of the octal number, preceded by ' 0x ' or ' 0X ' in hexadecimal (depending onUsing ' x ' or ' x ')0 The number shown is preceded by ' 0 ' instead of the default space% ' percent ' output a single '% '(VAR) mapping variable (dictionary parameter)M.N m i

With the rapid development and progress of Internet technology in China and abroad, Python has been used in the fields of automated operation and maintenance, automated testing, financial quantification strategy analysis, data analysis, crawler development, web site development, scientific computing, and the gap of Python programmers on the market. It also prompted many people to start learning

are using the functions defined in module ex25 . Try to do help (ex25) and help (ex25.break_words) . This is how you get the module help documentation. The so-called help document is what you put in the "" "when you define a function, and they are also known as documentation comments (document annotations), and you'll see something more like that later. Type ex25 repeatedly. It's a very annoying thing. A shortcut is to import the module using the from ex25 import * method. It's equiv

knowledge help you with your list operations? Very simply, every time you say "I want a 3rd animal" to yourself, you need to convert the "ordinal" to "base", as long as the former minus 1 is OK. The index of the 3rd animal is 2, which is penguin. Since you've been dealing with ordinals all your life, you need to get the cardinality in this way, as long as you've lost 1.Remember: ordinal = = ordered, starting at 1; cardinal = = Randomly selected, star

? True or False True True or True True False or True True False or False False and true? True and false False True and true true False and True Td>false false and False false not OR true?

. - - """% (like, age)The results are as follows: (performed under PowerShell)Ps:1. Pydoc in Windows usage, must go into the Python installation directory, execute python-m pydoc raw_input; (Of course you can replace the raw_input with other modules, such as Open, OS,)Here is the exercise code for Exercise 14:1 fromSysImportargv2 3Script, user_name =argv4prompt ='>'5 6 Print "Hi%s, I ' m the%s script."%(u

this script with Raw_input, think of the way to get the file name better, and why.6. Run Pydoc file to scroll down until you see the read () command (function/method). See a lot of other orders, you can find a few to try. No need to look at the commands that contain __ (two underscores), these are just rubbish.7. Run Python again at the command line to open a file, this open and read method is also worth l

line, and clarify your ideas for yourself. Even if you can't clear your mind, you can also know exactly where you really didn't understand. Write a script similar to the one in the previous exercise and read the file you just created, using Read and argv . There are too many places to repeat in the file. Try to print line1, line2, line3 with a target.write () , you can use strings, format characters, and escape characters. Find out why we need to give open multiple a ' W ' paramete

!" - Else: - Print "Well , doing%s is probably better. Bear runs away."% Bear - + elifDoor = ="2": - Print "You stare to the endless Abyss at Cthulhu ' s retina." + Print "1. Blueberries." A Print "2. Yellow jacket clothespins." at Print "3. Understanding revolvers yelling melodies." - -Insanity = Raw_input (">") - - ifInsanity = ="1" orInsanity = ="2": - Print "Your body survives powered by a mind of Jello.

mistaken. You need a way to tell that the double quotes inside the Python string are not true double quotes.To solve this problem, you need to escape the double and single quotes, and let Python enclose the quotation marks in the string. Here's an example:The second method is to use "three quotation marks (triple-quotes)", or "" ", you can put any number of line

Exercise 32: Loops and ListsNow you should be able to write more interesting programs out. If you can keep up with it, you should have seen that combining "if statement" and "Boolean expression" can make the program do something intelligent.However, our program also needs to be able to do the repetitive things quickly. In this exercise we will use For-loop (for loop) to create and print a wide variety of lists. In the process of doing this, you will gradually understand how they are going. Now I

,%r tall,and%r heavy. "% (age,height,weight)#exercise12 prompting othersY=raw_input ("Name?") #这句话会用 "Name" prompts the user and assigns the result of the user input to the variable Y.#这就是我们提问用户并且得到答案的方式.Age=raw_input ("How old is You?")Height=raw_input ("How Tall is You?")Weight=raw_input ("How much does you weigh?")Print "So" is%r old,%r tall,and%r heavy. "% (age,height,weight)#exercise13 parameters, unzip, variableFrom sys import ARGVScript, first, second, third = argvPrint "The script is cal

find a problem with the map, adjust the map so that the code and the map match each other.One last suggestion: Every programmer will be influenced by irrational fears when they start a big new project. In order to avoid this fear, they will stall time and end up doing nothing. I sometimes do that, everyone has this experience, the best way to avoid this situation is to make a list of what you want to do, one time to complete the same.Start doing it.

explain the meaning of the code to yourself through annotations. Explain how each function is used, the purpose of each variable, and any other aspect of the content, as long as it helps you to understand the code.Finally, each part of the code that is difficult to track, line-by-row or function-by-bit tracking variable values. You can print one more copy and write the value of each variable you want to "track" in the blanks.Once you have a basic understanding of the function of the code, go ba

? What happens if you don't indent? Is it possible to put the other Boolean expressions in Exercise 27 in the "if statement"? Try it. What happens if I change the initial value of the variable people, Cats, and dogs ? Exercise Exercises1.The IF statement.if sentence1: sentence2The sentence one is the judgment part , of course, it can also be a Boolean expression of the previous lesson.The white space in front of the statement two is also part of the IF statement, and using i

":Return ' death 'elif action = = "Slowly Place the bomb":Return ' Escape_pod 'ElseReturn ' The_bridge 'def escape_pod (self):Good_pod = Randint (1,5)Guess = Raw_input ("[Pod #]>>>")if int (guess)! = good_pod:Return ' death 'ElseExit (0)Class Engine (MAP):def __init__ (Self,start):Self.start = Startdef play (self):Next = Self.startWhile True:print "\ n-----------"GetAttr (Self,next)Next = Guest ()A_game = Engine ("Central_corridor")A_game.play () Remark: Beginner young novice, Welcome to the gre

commas (comma). Just like you go to the store and say, "I want to buy milk, bread, eggs, eight treasures porridge," just as programmers say "(milk, eggs, bread, soup)."We will type a large number of strings, variables, and formatting characters, and print them out. We'll also practice using the shorthand variable name. Programmers like to use shorthand for annoying difficulty to save typing time, so let's learn this early so that you can read and wri

done."Out_file.close ()In_file.close ()#另一种写法 (only one line):From sys import ARGVScript,from_file,to_file = argvOpen (To_file, ' W '). Write (open (from_file). Read ())Exercise: naming, variables, code, functionsWhat are the rules for function names?As with the variable name, it can be as long as it consists of alphanumeric and underscore, and not the number beginning.What does it mean to be *args *?Its function is to tell Python to accept all the p

It seems that the following is the most elegant implementation.Other, either node redundancy, or initialize ugly ...#!/usr/bin/env python#-*-coding:utf-8-*-classNode:def __init__(self, initdata): Self.__data=InitData self.__next=NonedefGetData (self):returnSelf.__data defGetNext (self):returnSelf.__next defSetData (Self, newdata): Self.__data=NewDatadefSetnext (Self, newnext): Self.__next=Newnextclasssincyclinkedlist:def __init__(self): Self.head=No

The 32-33 chapters will be for-loop and while-loop loops.The two kinds of syntax will not be said. Simply say the individual's understanding for and while.I think he learn python.First say the same point:1, can not do a single operation, For-loop if the collection is empty, the condition behind the while is false he can also do a loop operation is not done, the test method is as follows:　　 for inch []: Print " 1 " , I, 　　　 While I : Print 1