PROGRAMMING IN PYTHON LETS LEARN SOME CODE TOGETHER

PROGRAMMING IN PYTHON LETS LEARN SOME CODE TOGETHER!

CHALLENGE • If you know how to make games in Python, your task it to surprise us with what you can come up with. • If not we are going to create a few games together in Python now.

PYTHON CAN DO SIMPLE MATHS Python uses these symbols to do simple Maths, what do you think each one does? + / - *

VARIABLES • What’s a variable? • Something that is stored for later use and can be called if needed. • Variables can be any data type.

LETS GIVE IT A TRY

STRINGS • Variables can contain text too, these are called strings. • We use quote marks to set what text the variable will hold. • Variable = ‘ text ‘

LETS GIVE IT A TRY

LETS MAKE OUR FIRST SIMPLE PROGRAM

WHAT WILL IT DO? • Together we will make a program to say hello and ask for a name. • It will then use the name that is inputted to say, it is good to meet you (name).

SHALL WE SHOW YOU WHAT YOU WILL BE CREATING?

STEP 1 • Click on File, New Window. • This is the File Editor. • Click Save and save it as Hello World in your user area. • Make a folder called Python to put it in if you want.

# TAGS • A # tag can be used to write a comment to anyone who reads your code. • Try this now, tell the reader what the program will be doing.

PRINT COMMAND • What do you think a print command might do? • It prints whatever you ask it to onto the screen of the user. • Just like strings the text needs to have quote marks around it but also needs to

LETS GIVE IT A TRY

BY NOW YOU SHOULD HAVE SOMETHING LIKE THIS… # This program says hello and asks my name. print (‘Hello World’) print (‘What is your name? ’)

ADDING A VARIABLE • Now we need a variable to hold a name value.

INPUT COMMAND • The input command will take what the user inputs into the program. • It can be used to put inputted text into a variable. • It looks like this: Name = input ()

LETS GIVE IT A TRY

NOW WE CAN USE THE NAME TO SAY HELLO… • Try to work out how you might do this. • You need the print command, the + symbol, the variable and the other symbols needed in each command e. g. ‘ ‘ ( ).

BY NOW YOU SHOULD HAVE SOMETHING LIKE THIS… # This program says hello and asks my name. print (‘Hello World’) print (‘What is your name? ’) name = input() print (‘It is good to meet you, ‘ + name)

LET’S RUN THE PROGRAM! • Save the program again. • Click Run, Run Module. • The program should start. • If it errors there is a mistake in your code, try to fix it yourself, if you cant ask a friend, as a last resort ask a teacher.

LETS MAKE A HARDER GAME…

WHAT WILL IT DO? • This game will ask the users name and ask them to play a guess the number game. • The user will have 6 guesses, but they will be told if they are guessing too high or low. • Once they guess correctly it will tell them

SHALL WE SHOW YOU WHAT YOU WILL BE CREATING?

STEP 1 • Click on File, New Window. • This is the File Editor. • Click Save and save it as Guess the Number in your user area. • Make a folder called Python to put it in if you want.

# TAG TIME • Write a # tag comment to anyone who reads your code.

IMPORT • Type import random • This imports several functions related to random numbers. • We will come back to this later.

VARIABLE • Set a variable guesses. Taken to 0.

ASK FOR THEIR NAME • Ask for their name and remember to tell the computer to add it to a variable called name using, input()

SETTING THE NUMBER TO BE FOUND • To do this we need a variable called number and the random statement again. • Type in the following: number = random. randint (1, 20) This asks for the computer to import a random integer (number) between 1 and

BY NOW YOU SHOULD HAVE SOMETHING LIKE #THIS… This program is a guess the number game. import random guesses. Taken = 0 print (‘Hello! What is your name? ’) name = input() number = random. randint (1, 20)

USE THE NAME VARIABLE • Use the name variable to tell the player you are thinking of a number between 1 and 20.

WHILE LOOPS • What is a while loop? • A while loop will perform an action (set by you) while a condition is being met (also set by you). • We need a while loop that asks the player to take a guess while the number of guesses taken is less than 6.

WHILE LOOPS while guesses. Taken <6: print (‘Take a guess’) # indent this line by 4 spaces

GUESS VARIABLE • Now we need a guess variable that will contain what the user inputs. • How might we do this?

SETTING THE INPUT TO AN INTEGER • The input at the moment will be classed as a string of text, even though we know it is a number the computer does not.

SETTING THE INPUT TO AN INTEGER We need to tell the computer that the inputted data is an integer. This is how we do it: guess = int(guess)

TELL THE COMPUTER THE USER HAS MADE A GUESS • Now the computer needs to increase the variable guesses. Taken by 1. • How might we do this? guesses. Taken = guesses. Taken + 1

BY NOW YOU SHOULD HAVE SOMETHING LIKE THIS… number = random. randint (1, 20) print (‘Well, ‘ + name + ‘, I am thinking of a number between 1 and 20. ’)

BY NOW YOU SHOULD HAVE SOMETHING LIKE THIS… To tell the while guesses. Taken < 6: computer the print (‘Take a guess’) while loop is still running guess = input() we must guess = int(guess) indent all of guesses. Taken = guesses. Taken + 1 the content

IF STATEMENTS • An if statement will tell the computer to do something if a condition has been met, if it has not it wont compete the command set by you. • There are other types of if statements. Can you think of any?

IF STATEMENTS == means equal to The if statements print (‘Your guess is too low’) are indented if guess > number: by 4 spaces and the print (‘Your guess is too high’) contents of if guess == number: the if break statements if guess < number:

THE WHILE LOOP IS OVER! • All code should now start without an indent.

SO ONCE THE GUESS LIMIT IS REACHED, WHAT HAPPENS?

IF THEY GUESSED CORRECTLY • Think how we could use an if statement to do a command if they guessed correctly. if guess == number:

WHAT WOULD THE COMPUTER DO? • First we need the convert the number of guesses back into a string so we can display it for the user. • How might we do this? guesses. Taken = str(guesses. Taken)

THEN CONGRATULATE THEM AND TELL THEM THEIR GUESSES print (‘Good job, ‘ + name + ‘! You guessed the number in ‘ + guesses. Taken + ‘guesses!’)

IF THEY GUESSED INCORRECTLY • Think how we could use an if statement to do a command if they guessed correctly. != means not equal to. if guess != number:

WE CONVERT THE NUMBER VARIABLE • This time we convert the random number chosen at the start into a string so we can display it. • How might we do this? number = str(number)

THEN TELL THEM THEY WERE NOT SUCCESSFUL! print (‘Nope, the number I was thinking of was ‘ + number)

BY NOW YOU SHOULD HAVE SOMETHING LIKE THIS… Notice the if guess == number: guesses. Taken = str(guesses. Taken) indents! print (‘Good job, ‘ + name + ‘! You guessed the number in ‘ + guesses. Taken + ‘guesses!’)

BY NOW YOU SHOULD HAVE SOMETHING LIKE THIS… Notice the if guess != number: number = str(number) indents! print (‘Nope, the number I was thinking of was ‘ + number)

CONGRATULATI ONS YOU HAVE MADE YOUR GUESS THE NUMBER GAME!

LET’S RUN THE PROGRAM! • Save the program again. • Click Run, Run Module. • The program should start. • If it errors there is a mistake in your code, try to fix it yourself, if you cant ask a friend, as a last resort ask a teacher.