Cheatography

# Nancy's Python Cheat Sheet by mnasnan

### Naming Convention

 Rule for giving name - letter - numbers - underscore _ Valid name - _myStr - my3 - Hello_­​there Invalid name - 3my=”hi” -- cannot start with number - first name=”hi” - first-name - first+name

### Symbol

 == Equal != Not equal >= More than or equal <= Less than or equal % (Madulo) Find the remainder

### Multip­­li­c­ation and Exponents

 string * number Combine that string string* string CRASH! number * number Multiply (Math) string ** string CRASH! number ** number Exponent (Math) string ** number CRASH!

### Area of Triangle

 ``````def areaOfTriangle(base, hight) :     return 0.5 base hight user_base = float(input("Enter the base of the triangle: ")) user_height = float(input("Enter the hight of the triangle: ")) print ("The area of the triangle is", areaOfTriangle(user_base, user_height)) def volumeOfPrism(area, high) :     return area * high user_prism_high = float(input("Enter the hight of the prism: ")) print ("The volume of the prism is", volumeOfPrism(areaOfTriangle(user_base, user_height), user_prism_high))``````

### Reverse Word

 ``````while True:     word = input("Please enter a word")     index = 0     reverse = ' '          while int(index) < len(word):         reverse = word[index] + (reverse)         index = int(index) + 1     print ("Reverse: ", reverse)``````

### Sort fruit list

 ``````fruits = [] #an empty list for number in range(5):     user_fruit = input("Please enter a fruit")     fruits.append(user_fruit) print ("Size of fruit list is", len(fruits)) fruits.sort() for fruit in fruits:     print ("Fruit: ", fruit)``````

### Countdown Machine

 ``````number = int(input("What number do you want to count down? ")) countdown_string = ' ' while number > 0:     countdown_number = countdown_string + str(number) + " "     number = number - 1     print (countdown_string)``````

### Area of Circle

 ``````user_radius = input("What is a radius of a circle?") radius = float(user_radius) pi = float(3.1415) area = pi(radius*2) print ("The area of the circle is", area)``````

### Create List

 ``````create a function name: createList argument: quitword return: a list def createList(quitword):     mylist = [] #empty list     while True: #loop forever         user_word = input("Please enter a list item: ")         if user_word == quitword:             return mylist #returns the list and exits the function         duplicateword = False         for item in mylist:             if user_word == item:                 duplicateword = True         if (duplicateword == True):             print ("Duplicate Word!")         else:             mylist.append(user_word) #Adds the user_word to the end of the list        userlist = createList('stop') #Function Call print (userlist)``````

### Function (Ex.)

 ``````def myprint2(text, decoration): #Text and decoration is a parameter     print (decoration + str(text) + decoration)     return myprint2("Hello", "+++++") myprint2("Hello", "-=-=-=-=") myprint2("Hello", "<<<<<")``````
+++++H­ell­o+++++
-=-=-=­-=H­ell­o-=­-=-=-=
<<<­<<H­ell­o<<­<<<

### Palindrome

 ``````def isPalindrome(word):     index = 0     reverse = ''     while int(index) < len(user_word):         reverse = user_word[index] + (reverse)         index = int(index) + 1     if user_word == reverse:         return True     else:         return False while True:     user_word = input("Please enter a word: ")     if user_word == "quit":         break          print("Length of the", user_word, "is", len(user_word))                  Palindrome = isPalindrome(user_word)     if Palindrome == True:         print (user_word, "is a Palindrome!")     else:         print (user_word, "is not a Palindrome")``````

### Sort word per line

 ``````mystr = "Hello" letter_num = 0 while letter_num < len(mystr):     print (mystr[letter_num])     letter_num = letter_num + 1``````

### Convert decimal to binary

 ``````user_number = ' ' while user_number != ' 0 ' :     user_number = input ("Enter a number to convert to binary")     number = int(user_number)     binary_string = ' '     while (number > 0):         remainder = number%2         binary_string = str(remainder)+ binary_string         number = number//2     print ("Binary string is", binary_string)``````

### Area of Circle by Function

 ``````def areaOfCircle(r):     pi = 3.1415     area = pi r * 2     return area user_radius = input("Enter the radius of the circle: ") radius = float(user_radius) print("The area of the circle is", areaOfCircle(radius))``````

### Guess word game

 ``````import random guesslist = ['grape', 'orange', 'chloroplast', 'ribosome', 'lipstick'] chance = 3 score = 0 print (guesslist) while chance != 0:     random_item = random.choice(guesslist)     user_input = input("Please guess a word: ")     if user_input == random_item:         print ("That's correct!")         score = score + 100         print ("Score:", score)     else:         if user_input not in guesslist:             print ("Sorry, that isn't even in the list!")             chance = chance - 1             print ("Chance Remaining:", chance)         else:             print ("Sorry, wrong choice!")             chance = chance - 1             print ("Chance Remaining:", chance) if chance == 0:     print ("The word was", random_item)     print ("The score is", score)``````

### Convert binary to decimal

 ``````num = str(int(input("Enter a binary to convert to decimal "))) dec = int(num, 2) print ("The decimal number is", dec)``````