"""This tutorial will show a lot of basic input/output functions and methods so that
you can start your python programming journey. It wil focus on efficiency and won't
be too complex, there will be more advanced tutorials on my channel in future, so be
sure to like and subscribe."""
#The first in-built function you need to know is print
print("Hello world")
"""This will allow you to display a piece of text of your choosing to the screen,
in this app it will display to the window on the right -->"""
#Now I will run the program
#So now let's do something a bit more advanced
#let's say we want to store something in memory then print it
#We use a variable, you can name it whatever you want, but it should be descriptive
name = "John"
"""That is one example of a variable, now we can use it to print the name of someone,
however, it doesn't need to be the only thing in the print statement, you can use a comma,
to seperate the name and any text you want to put in as well"""
print("My name is:",name)
#Okay, so we printed out some text, we can also print out numbers
age = 7
#Now let's try to print this age directly
print("My age is:",age)
#However, what if we want to add 2 numbers and print the result
num1 = 23
num2 = 5
print(num1+num2)
#This time the numbers will be in quotes
num3 = "3"
num4 = "5"
#Write in the comments what you think will happen
#Anyways, let's print out the 2 numbers
print(num3+num4)
#We can use another function 'int' to convert them to numbers
print(int(num3)+int(num4))
#So that was output, what about input, when we want to enter a value
#There is another function for this, 'input'
text = input("Enter something: ")
print("you entered:",text)
#We can also put some text inside the input function
"""There are also other ways of inputting text and you can input mnore than just text,
however that is more advanced and requires more tools, we will explore them in
future tutorials, anyways let's try to input a number"""
num = int(input("Enter a number: ")) #We can use int to convert them to numbers
otherNum = int(input("Enter another number: "))
print("The sum of the numbers is:",(num+otherNum))
"""However, a comma is usually better as it automatically adds a space between text in
quotation marks and a variable"""
"""Now we can put everything together to make something"""
name = input("Enter your name: ")
age = int(input("Enter your age: "))
anotherAge = int(input("Enter someone else's age: "))
print("Your details are:\nYour name is:",name,"\nYour age is:",age,
"\nYou are",(age-anotherAge),"years older than this other person")
Tutorial - part 2
#Today we will be looking at String methods and conditional statements
"""This program will closely examine some of the various string methods and also
will look at conditional statements (if, elif, else) and also the boolean operators"""
#below is an example of a string
myString = "Hello, This is a string!"
#First we'll start with string slicing
print(myString[:5]) #This will print out the first 5 characters of 'myString'
print(myString[10:]) #This will print from character 10 till the end
print(myString[6:11]) #This will print from character 6 until character 10 (not including 11)
#You can also get a single character from a string, this time we'll ask the user
character = int(input("Enter a character number (index) to retrieve from string: "))
print("The character is:",myString[character])
#Okay, so now we will use one of the many string methods
print(myString.count('s'))
#This will print out the amount of times a certain character appears in our string
#Now we can use a different method
newString = myString.replace('Hello', 'Bye')
print(newString)
#So this will replace any substring with another substring, you have to store it as a new string
#There is also a 'lower' method and 'upper' method
print(myString.lower())
print(myString.upper())
#Now moving onto if statements (conditional statements)
if myString.islower() | myString.isupper():
print("String is uniform")
else:
print("String is irregular")
#Let's do an example with numbers
num1 = int(input("Enter a number: "))
num2 = int(input("Enter another number: "))
if (num1 > 5) & (num2 <= 5):
print("Success")
elif (num1 == 5) | (num2 > 5):
print("Neither a fail nor a success")
else:
print("Fail")
otherString = input("Enter a string to compare to myString: ")
if (myString.islower() | myString.isupper()) & (otherString.islower() | otherString.isupper()):
print("Both strings are regular")
elif not (myString.islower() | myString.isupper()) and not (otherString.islower() | otherString.isupper()):
print("Both strings are irregular")
else:
print("The strings aren't similar in terms of case")
if myString[:5].lower() in otherString.lower():
print("Both are greetings!")
else:
print("One of the strings is not a greeting")
if myString == otherString:
print("The strings match!")
else:
print("The strings don't match")
Tutorial - part 3
"""Ok so I've explained a bit about iteration loops and file handling, now we will
move on into the coding examples, be sure to follow along if you're watching
from home and want to learn python"""
"""#In a for loop, we don't need any pre-defined variables
for num in range(5):
print("The number is:",num)
#This will print out the numbers from 0 to 4 (not including 5)
#For loops are very useful, but only if we know the amount of times we're looping
for i in range(1,6):
#here we are looping from 1 to 5 (not including 6)
print("I have",i,"apples")
#Anyway now let's look at counting backwards
for count in range(5, 0, -1):
#-1 will allow us to go backwards by 1 each time
print("Numbers till countdown ends:",count)
#We can also loop in increments, for example every even number (up to a point)
for number in range(0, 22, 2):
#This will print out every even number from 0 to 20
print("The even number is:",number)
#The final thing we can do with for loops is loop over data structures such as lists
#First we will create the list
myList = list(range(0,10)) #This is a handy trick for creating a list quickly
#Now we will print each number in the list
for item in myList:
print("The item is:",item)
#Now moving onto while loops, for these we do need pre-defined variables
continueLoop = True
while continueLoop:
continueLoop = input("Should the loop continue? ")
if continueLoop.lower() == "yes":
continueLoop = True
else:
continueLoop = False
#Here we took a user input then assigned values to it using an if statement
#If you haven't already, check out the previous tutorial where we went over if statements and string methods
#Now we move onto file handling, this also uses loops
#First we will read a file using a for loop
#We need to open the file and we use the "open" command for this
thisFile = open("new.txt")
#This will open the file in read mode that is called "new.txt", the file format does have to be there
#Now we can print each line of the file
for line in thisFile:
print(line)
#Another way to open a file is to store its name in a variable
fileName = "newer.txt"
file = open(fileName)
#There are also other methods to read from the file
fileContents = file.readlines()
for line in fileContents:
#There is also another method (split) which can split a line by any character
line = line.split(",") #In this example, we have a comma seperated list on each line
#This method will return an array
#Now we can use a for loop to iterate through each item in the line list/array
for item in line:
print(item.strip())"""
#Now we will write to a new file, you don't need an existing file for this
fileName = input("Enter a name for the file: ")
#We have to append the txt extension to the filename, otherwise it won't work
fileName += ".txt"
#Whoops, almost forgot to open the file
myFile = open(fileName, 'w') #We need the 'w' to be able to write to the file
#Now we can use a while loop to let the user keep adding to the file
moreLines = True #remember, we need a pre-defined variable
while moreLines:
line = input("Enter a line to add to the file: ")
moreLines = input("Do you wish to add more lines(Y/N)? ")
if moreLines.upper() != "N":
moreLines = True
else:
moreLines = False
#Now we can write the line to the file
myFile.write(line)
myFile.write("\n")
#Finally, we have to close the file
myFile.close()
Tutorial - part 4
"""We'll begin by creating a few functions or procedure for functional programming
Here's a simple example"""
def add(num1: int, num2: int) -> int: #over here we've declared a function with type hints (variable types)
total = num1 + num2
return total #the return keyword is key in functions
def subtract(num1: int, num2: int) -> int: #this is a subtract function similar to the add one above
difference = num1 - num2
return difference
def main(): #this one is a procedure so won't return anything
num1 = int(input("Enter a number: ")) #here we take the first number as a user input (covered in episode 2)
num2 = int(input("Enter another number: "))
total = add(num1, num2)
difference = subtract(num1, num2)
#above we just called the 2 functions we defined above with the numbers, now we can output the results
print("The total of the 2 numbers is:",total)
print("The difference between the 2 numbers is:",difference)
#now we'll use the main statement and call our procedure
if __name__ == "__main__":
main() #now we run it
"""So in this example, we have the add and subtract functions
that perform basic arithmetic operations and then the main procedure
calls these functions after taking user inputs and presents the results in
an orderly and user friendly manner. It's an easy model to follow and straightforward for simple tasks.
However, in a real world situation, it isn't always ideal and that's where OOP comes in."""
# Now in OOP we'll use classes to build the calculator and define it in code
class calculator():
def __init__(self): #this is the constructor method, it's needed in all classes
#we'll use this to 'save' variables
self.num1 = 0 #this is a public attribute (can be accessed anywhere)
self.__num2 = 0 #the 2 underscores transform it into a private attribute (can only be accessed within this class)
#now we've set up variables as attributes
def __add(self): #here we've setup a private method
return self.num1 + self.__num2
def __subtract(self):
return self.num1 - self.__num2
def calculate(self, num1, num2):
self.num1 = num1
self.__num2 = num2
total = self.__add()
difference = self.__subtract()
#above here, we've called the 2 private methods wee defined before and set the attributes to the passed in variables
return total, difference
if __name__ == "__main__":
thisCalculator = calculator() #this is where we instantiate the class
num1 = int(input("Enter a number: "))
num2 = int(input("Enter another number: "))
total, difference = thisCalculator.calculate(num1, num2) #the method is then called here
print("The total of the 2 numbers is:",total)
print("The difference between the 2 numbers is:",difference)
"""In this OOP example, we defined a Calculator class with methods add and subtract.
We then created an instance of the Calculator class and call its method.
This modular approach is great for more complex projects where you want to encapsulate data and behavior.
It also allows for methods that can't be accessed anywhere else, minimising unintended side effects"""
Tutorial - part 5
from colorama import init, Fore
#This class will be used to load the flashcards from the file and includes all associated methods
class FlashCardLoader():
def __init__(self, initial_filepath):
self.__cards = [] #List that will store the flashcards after loading
self.__filepath = initial_filepath #Filepath for the text file that stores the questions and answers
self.__delimiter = "," #Delimiter that is used in the file to separate questions from answers
def load_cards(self): #This method will load the cards from our text file
try: #Here we're using exception handling - this enables us to catch potential runtime errors before they happen
with open(self.__filepath, "r") as file: #This is a set construct used to read a file (without having to use file.close() afterwards)
self.__cards = file.read().splitlines() #The file is read and each 'card' is put into a separate index in the cards list
for i in range(0,len(self.__cards)): #We use a for loop to iterate through the cards list
current_card = self.__cards[i] #We store the current card in a variable for easier access
#We split the current card into question and answer using the delimiter and update the cards list accordingly
self.__cards[i] = current_card.strip().split(self.__delimiter) #We use the strip method also to remove any leading or trailing whitespace from each card
print(self.__cards) #For testing purposes we print out the cards list to verify it's loaded correctly
except FileNotFoundError: #Here we catch the error if the file isn't found and define what to do next
print("Flashcards file not found.") #We just simply print out a relevant statement in this case
def get_cards(self): #An accessor method is used here to retrieve the cards list from the class
return self.__cards
def get_filepath(self): #An accessor method is used here to retrieve the file path from the class
return self.__filepath
def get_delimiter(self): #An accessor method is used here to retrieve the delimiter from the class
return self.__delimiter
def set_delimiter(self, new_delimiter): #A mutator method is used here to change the delimiter used within the class
self.__delimiter = new_delimiter
def set_filepath(self, new_filepath): #A mutator method is used here to change the file path used within the class
self.__filepath = new_filepath
#This class will be used for the main flashcard logic and will encompass the following functions:
"""
1. Looping through flashcards when revising
2. Quizzing yourself on existing flashcards
3. Adding new flashcards temporarily (to the list at runtime but not to the saved text file)
4. Evaluating answers from the flashcards quiz
5. Tracking your score when attempting a quiz
"""
class FlashCardEngine():
def __init__(self):
self.__cards = [] #Store the cards that are loaded in a list
self.__user_choice = 0 #Update this when the user choice input is taken
self.__score = 0 #Store the score for the quiz
#Use a dictionary to store the menu options that the user can select
self.__menu = {1: "1. Loop through flashcards", 2: "2. Add new flashcards temporarily", 3: "3. Quiz yourself on the current flashcards", 4: "4. Quit"}
#Method to display the different menu items
def display_menu(self):
for item in self.__menu.items(): #Uses a for loop and dictionary items method to loop through the menu
print(item[1]) #print the relevant menu item
#Method to take user input and verify it
def get_user_choice(self):
print("Choose an option from the menu above")
max_choice = max(list(self.__menu.keys())) #Uses the max, list and dictionary keys method to find the highest choice number available
choice = input(f"Enter your choice as a number between 1 and {max_choice}: ") #Takes the choice as a number between 1 and max_choice
choice_valid = self.check_user_choice(choice) #Calls the below method to check if the user choice is a valid number
if choice_valid: #An if statement to activate when the choice is valid
self.__user_choice = int(choice) #sets the user_choice attribute that's mentioned in class constructor
return True #returns True to signify that the choice is valid
else: #If the choice isn't valid - handles it likewise
print("Please enter a valid choice") #Issues a user warning via print statement
return False #returns False to signify that the choice isn't valid
#Method to check if the user's choice is a valid number
def check_user_choice(self, choice):
try: #Here we use exception handling once again - we need to check if the choice is a number
user_choice = int(choice) #To achieve this we use type casting (explored in episode 2 or 3) and convert it to a number
except ValueError: #If the type casting failed we'll receive this error and can catch it
return False #We return False if it can't be converted to signify that the choice is invalid
# Now we need to check if the choice is part of our available options - we can use the menu dictionary for that
if user_choice not in list(self.__menu.keys()): #Specifically the .keys method allows us to check the menu options
return False #We return False as even though the number conversion check passed, the menu option is invalid e.g. 5
else: #Otherwise, all checks have passed and we can assume the user entered a correct number for their menu choice
return True #We return True to signify that the user input is valid and can then progress to setting the user_choice attribute (in the above method)
#Method to call the different menu options depending on the user's choice
def use_menu(self):
if self.__user_choice == 1: #If the choice is 1, we activate this statement
self.display_flashcards() #We can call the method to display the flashcards (defined below)
elif self.__user_choice == 2: #If the choice is 2, we activate this statement
self.add_new_flashcards() #We can call the method to add new flashcards (defined below)
elif self.__user_choice == 3: #If the choice is 3, we activate this statement
self.attempt_quiz() #We can call the method to attempt the flashcards quiz (defined below)
else: #Otherwise we know that the user wants to quit - as there's no other options - for more options, more statements could be added as above
print(Fore.YELLOW + "Thanks for using the Python Programmer Flashcards System!")
quit() #This method stops the programme from running and ends the process automatically
#Method to display all flashcards currently stored in memory
def display_flashcards(self):
for card in self.__cards: #We use a for loop to read all the flashcards from the cards list (stored as private attribute)
print(f"Question: {card[0]}") #Prints out the question (stored as the first part of the flashcard)
input("Press Enter to view answer: ") #We allow the user to press enter before viewing the answer instead of giving it straight away
print(f"Answer: {card[1]}") #Prints out the answer of the flashcard (stored as the second part)
#Method that allows users to add new flashcards temporarily
def add_new_flashcards(self):
cards_to_add = 0 #We set this variable to 0 to begin with
try: #Once again we use exception handling - this time to make sure that cards_to_add is a number that can be used in the for loop
cards_to_add = int(input("Enter the number of flashcards to add to the list: ")) #We take this as user input and cast to integer directly
except ValueError: #If a ValueError occurs (i.e. it's not an integer) then we can handle it here
print("Please enter a valid integer.")
self.add_new_flashcards() #Here we call this method again to take the input again and then progress
for num in range(cards_to_add): #We use a for loop to keep allowing the user to enter new cards for as many cards as they said before
print("Question",num+1) #We print the question number that the user is adding (e.g. 1 if on the first one)
question = input("Enter your question: ") #We use a user input to get the question
answer = input("Now enter your answer: ") #Aother user input is used to get the answer to the question
self.__cards.append([question, answer]) #The question and answer are appended to the cards list
if cards_to_add != 0: #If there were cards added then we can proceed with this part
print(f"All {cards_to_add} flashcards have been added to the list.")
view_list = input("Do you wish to view the full cards list now (Y/N)? ") #We allow the user to view the cards list via user input
if view_list.lower() == "y": #If they chose to view the cards we can progress with this part
print("All cards in the list are displayed below:")
for card in self.__cards: #We use a for loop to read the cards list
print(f"Question: {card[0]}") #We print out the question as the first part of the flashcard
print(f"Answer: {card[1]}") #We print out the answer as teh second part of the flashcard
else: #Otherwise there either weren't any cards added or there was an error and we can handle that here
print("No flashcards added")
#Method to allow the user to quiz themselves on the flashcards
def attempt_quiz(self):
#This will mostly be where we will use the special colours from colorama to make it look nice
self.__score = 0 #We set the score to 0 first for every new quiz
for card in self.__cards: #We use a for loop to read the cards for the quiz
print(f"Question: {card[0]}") #We print out the question first (as first part of the card)
answer = input("Enter your answer: ") #Then we take the user's answer as user input
if answer.lower() == card[1].lower(): #If the answer matches (we use .lower to ignore the case) we can progress here
print(Fore.GREEN + "Correct! " + card[1] + " is the correct answer.")
self.__score += 1 #We increase the score by 1
else: #If the answer is incorrect we can progress here
print(Fore.RED + "Incorrect. " + card[1] + " is the actual correct answer.")
print("Your current score is:",self.__score) #After each question we print the score
#After the quiz finishes we can print this
print(f"Quiz finished! You scored {self.__score} out of {len(self.__cards)} flashcards!")
#Method to get the current score (accessor method)
def get_score(self):
return self.__score
#Method to get the current cards list (accessor method)
def get_cards(self):
return self.__cards
#Method to set the current cards list (mutator method)
def set_cards(self, new_cards):
self.__cards = new_cards
# Main programme logic to run the flashcards system
def main():
init(autoreset=True) #Initialises colorama with autoreset to avoid color issues in terminal
print(Fore.CYAN + "Welcome to the Python Programmer Flashcards System!") #Prints a welcome message in cyan color
flashcard_loader = FlashCardLoader("flashcards.txt") #Creates an instance of the FlashCardLoader class with the specified file path
flashcard_loader.load_cards() #Calls the load_cards method to load the flashcards from the file
cards = flashcard_loader.get_cards() #Retrieves the loaded cards using the accessor method
flashcard_engine = FlashCardEngine() #Creates an instance of the FlashCardEngine class
flashcard_engine.set_cards(cards) #Sets the loaded cards into the flashcard engine using the mutator method
while True: #Main loop to keep displaying the menu until the user decides to quit
flashcard_engine.display_menu() #Displays the menu options
choice_valid = flashcard_engine.get_user_choice() #Gets and validates the user's choice
if choice_valid: #If the choice is valid, proceed to use it
flashcard_engine.use_menu() #Calls the method to execute the chosen menu option
# Run the main programme logic
if __name__ == "__main__":
main()
"""
Ok, so now we've got a fully working app.
However, there's still one little part left.
Remember we pip installed colorama at the start of this episode.
Now we'll add different colors to our print statements to make the app look a bit more visually appealing.
"""
Python Programmer