python conditional assignment

First, if Judgment statement#only if, at which time the condition is fulfilled, otherwise nothing is donescore= Int (Input ('>>:'))ifScore>90: Print('Excellent') #you can add an else statement to if, meaning that if the If judgment is false, then the content of the if is not executed and the content of the else is executed .score= Int (Input ('>>:'))ifScore>=90: Print('Excellent')Else: Print('Pass') #If you need to judge multiple conditions, you can use the elif (else if abbreviat

times in the previous chapters. However, the assignment operation in the Python language is much more interesting. For example, you can assign multiple values to multiple variables at the same time.>>> x,y,z = 1,2,3>>> print(x,y,z)1 2 3?? In the above code, the three-in-one is assigned the three variables of x, Y and z, and the values of the 3 variables are output. Using this feature in the

1 ImportRandom2 3 """4 #查看源代码日后爬虫用5 Import Urllib.request6 7 # Coding=utf-88 9 url = "http://www.baidu.com"Ten data = Urllib.request.urlopen (URL). Read () One data = Data.decode (' UTF-8 ') A - print (data) - the # Print practiced hand - x = 5/2 - y = 3/2 - + print (' x = ', x, ' \ n ', ' y ', y) - print (' x and y are%.1f,%.1f '% (x, y) respectively) + A for z in range (1, one): at print (' {0:5d} {1:5d} {2:4d} '. Format (z, z * z, z * z * z)) - - print ("What??" + "Water") - Print (5 + 8

elif statements(equivalent to the else if in C language)In Python, when we need to have more judgment, we tend to use a different syntax, that is, using elif:if Judging condition 1: executing statement 1 elif Judging condition 2: executing statement 2 elif Judging condition 3: executing statement 3 ...... Else : EXECUTE statement n Now that we have a task to complete, suppose there is now a score for you to rank as follows:

. Relationship of the same level while, for and elseThe else is executed if the number of times it is set is not interrupted by break in the while and for normal loop, but if the middle is broken, the Else statement will not be Executed.When the normal cycle ends:1Flag_exit =False2 while notflag_exit:3 Print("123")4 Print("456")5Flag_exit =True6 Else:7 Print("Bye")8 9 #OutputTen123 one456 aBye # after the normal loop is finished, execute the statement under Else.Break Exit Situatio

IfConditional judgment is to execute a program fragment when a condition is true, otherwise execute another.3if age >= 18: print(‘your age is‘, age) print(‘adult‘)else: print(‘your age is‘, age) print(‘teenager‘)So the basic format of the IF statement is:条件判断1>: 执行1>elif 条件判断2>: 执行2>elif 条件判断3>: 执行3>else: 执行4>If the statement is judged from the top down, if it is in a certain judgment True , the statement corresponding to the execution of the sentence, then ignore the remaining elif andels

A deep understanding of variable assignment in Python and a deep understanding of python Preface In Python, the variable name rules, like most other advanced languages, are affected by the C language. In addition, the variable name is case sensitive.Python is a dynamic type language. That is to say, you do not need to

,-1):... if i%2 = = 0:... print I... break...98 #从99 to 0 steps to 1, the first to meet the conditions to jump out of the loop, and not to print all, if there is no break will print allWhile True/break>>> while True:... word = raw_input (' Enter a word: ')... if not word:... break.. else:The. print ' the word is ' + word #当输入一个值时, will print the value and continue the loop request Enter a If Word does not enter, then jump out of the loopList Deduction---Light-weight loops:>>> [x * x for x in ran

#-*-Coding:utf-8-*-counter = + # Assignment integer variable miles = 1000.0 # float name = "John" # string Print Co unter Print miles Print name In the above example, 100,1000.0 and "John" are assigned to the COUNTER,MILES,NAME variable respectively. Executing the above program will output the following results: 100 1000.0 John assigning values to multiple variables Python allo

Novice programming partners will have some doubts about the use of deep-level copies, today we will combine the characteristics of the Python variable storage from the memory point of view to talk about assignment and depth copy ~ ~ ~The variable and its storage of the--python of preliminary knowledgeBefore we get into the details of

' , age ... Print ' Adult ' isadultThe If-else of PythonWhen the If statement determines that the result of the expression is True, the IF-contained code block is executed:if age >=: print'adult'What if we want to judge the age under 18 and print out ' teenager '?The method is to write another if:if age : print'teenager'Or use the NOT operation:if Not-age >=: print'teenager'Careful classmates can find that these two conditions are either "or", or meet the condition 1, or meet t

elements within the original object do not cause changes to the elements inside the copied object. In a complex object, the child object element of the original object changes, and the sub-object element inside the shallow copy object also changes, at which point the sub-object is equivalent to the image file and has an effect on the object referencing it, whereas in deep copy, because the deep copy is a copy of all the elements, So the change of the face object element in the original obje

variable definition and assignment? Is it a design defect ?", This is a pseudo-problem. I mentioned at the beginning that Python can be called "No variable". Therefore, when it comes to "Definition" and "defect", it is even more a penalty. The closure Design of python is indeed flawed. It is not just this place, but there are reference passing parameters, but th

The copy between deepcopy is the entire value, and the deepcopy does not change when the original value changesArray type copy, the copied value also changes, if it is a = [1,3] This full assignment, the original copy value will not change, if the value of each position of the array is assigned a new value (such as a[1] = 1,a[2] = 3)The main difference between copy () and Deepcopy () is how Python stores th

operational requirements and preliminary thinkingEmployee Information Form procedures, to achieve additions and deletions to check the operation:① can be used for fuzzy query , the syntax supports at least the following 3 kinds :Select Name,age from staff_table where > 22select * from staff_table where dept = ' IT ' select * from Staff_table whe Re enroll_date like "2013" ② solution : A python parsing problem with SQL statements that will con

the name, such as directly with accounts.• Name to make a meaningful distinction, sometimes you may use the name of A1,A2, it is best not to do so, in a separate way, by literal to see a certain distinction to better.• The best name can be read out, do not make their own English words, also do not use what is written, especially in your country, but also like to use Hanyu Pinyin abbreviation as the name, more trouble, than the whole fight it. It is best to use a complete word or a recognized ab

Conditional statements If we want to respond effectively to the user's input, the code needs to be able to judge. Can let the program to judge the structure becomes the condition, the condition Judgment statement returns the Boolean value TRUE or FALSE, actually executes one line, false executes another line Note If the IF judge what, otherwise do not do any action must write a pass or will errorsuch as :# !/usr/bin/env

One, Assignment (Assignment)>>> a = [1, 2, 3]>>> B = a>>> print (ID (a), id (b), sep= ' \ n ') 139701469405552139701469405552　　In Python, assigning a variable to another variable is actually adding a "label" to the object currently in memory.As in the example above, by using the built-in function ID (), you can see that a and B point to the same object in memory.

;>> b 4>>> A = b = []>>> b = [].append ('a')>>> a[] >>> ID (a)42958520>>> ID (b)1898129408Three. Printing>>> log = open ('Log.txt','a')>>> x ='x'>>> y ='y'>>> z ='Z'>>>Print(X,y,z,file =log)>>>log.close ()>>>Print(Open ('Log.txt'). Read ()) x y zThis chapter exercises:1. Give three ways to assign three variables to the same value.Answer: A,b,c = 1,1,1A=b=c=1A = 1;b = 1; c = 12. What do you need to be aware of when assigning three variables to a mutable object?Answer: a=b=[], a= a.append (), A is

Like many languages, Python is divided into "copy" Ways of simple assignments, shallow copies, and deep copies. In the learning process, the initial understanding of the shallow copy is very vague. But after a series of experiments, I found a better understanding of the three concepts. One, assign the value Assignment is the most common of these three operations, and we analyze the