Python – Tony Ballantyne Tech

Functions and Parameters (Level 6)

Sample Code

def hello(name):
    answer = "Hello " + name
    return answer

print(hello("George"))
print(hello("Gill"))

def AreaRect(length, width):
    return length*width

l = int(input("Enter the length"))
w = int(input ("Enter the width"))
print(AreaRect(l, w))

PI = 3.1415

def main():
    radius = 4
    print("The area of a circle radius ", radius, " is ", Area(radius))     


def Area(r):
    return PI*r*r

main()

Exercises

Write a function that accepts a string and returns “Pleased to meet you, ” + string
Write a function that accepts a number and returns “Child” if the number is <18 and “Adult” otherwise
Write a function that accepts a number and returns “Grade A” if the number is >20, “Grade B” if the number is >15, “Grade C” if the number is >10 and “Fail” otherwise.
Write a function that accepts two numbers and returns the average of the numbers
Write a function that accepts three integers and returns the average of the numbers.
Write a function that accepts the length and width of a rectangle and returns the perimeter of the rectangle
Write a function that accepts the base and height of a triangle and returns the area of the triangle
Write a function that accepts a list and returns the sum of the list

Extension

Write a function that returns the hypotenuse of a triangle when the other two sides are int a and int b. (Remember: hypotenuse squared equals a squared plus b squared)
The scalar product of u=(u1,u2,u3) and v=(v1,v2,v3) is defined to be u1v1+u2v2+u3v3. Write a function that accepts two int tuples as parameters and returns an int representing the scalar product of those two tuples
If A = (a1,a2, …an) and B = (b1,b2, …bn) then the vector sum of the two tuples A + B = (a1+b1, a2+b2, … , an+bn). Write a function that accepts two tuples as parameters and returns an array representing the vector sum of those two tuples
The Euclidean distance between two points A = (a1,a2, …an) and B = (b1,b2, …bn) is defined as sqrt((a1-b1)² + (a2-b2)² +… + (an-bn)²). Write a function that accepts two int tuples representing A and B as parameters and returns a double representing the Euclidean distance between them.

Data Types: int and float (Level 3)

Remember that the input command reads strings. You have to convert strings to integers (whole numbers) or floats (decimals) if you want to use them to perform calculations.

Examples

1) Write a program that prompts the user to enter the length and width of a rectangle. Output the area of the rectangle

length = int(input("Enter the length of the rectangle"))
width = int(input("Enter the width of the rectangle"))
area = length*width
print("The rectangle has an area of " + str(area))

2) To convert miles to kilometers, you multiply the number of miles by 1.609. Write a program that prompts the user to enter the number of miles, and then output the answer converted to kilometers

Note the use of float as a user may input 12.5 miles, for example.

miles = float(input("Enter the number of miles"))
kilometers = miles * 1.609
print(str(miles) + " miles = " + str(kilometers) + " kilometers")

Exercise

Write a program with two variables, length and width, that outputs the perimeter of a rectangle. Test it with length = 5 and width = 4.
At the time of writing, the exchange rate for pounds to euros is 1 GBP = 1.19984 Euros. Write a program that will convert pounds to euros. Test it using the data GBP4.50 (Don’t forget to convert the input to a float!)
Now write a program to convert euros to pounds. Test it using the data Euro 7.40
Prompt the user to input a number. Output the square of that number.
Prompt the user to input two numbers. Output the average of those two numbers.
Prompt the user to input three numbers. Output the sum and the average of those three numbers.
Assume pi = 3.1415. Prompt the user to input the radius of a circle. Output the circumference and the diameter of that circle

Extension: Fahrenheit to Celsius

Here are the formulas to convert from Fahrenheit to Celsius and back again.

°F to °C Deduct 32, then multiply by 5, then divide by 9 °C to °F Multiply by 9, then divide by 5, then add 32

Now write a program to convert Celsius to Fahrenheit. Use the test data to check your program.
Write a program to convert Fahrenheit to Celsius. Again, use the test data below to check your program.

Test data

C	F
0	32
12	54
100	212
-3	27
-18	0
-23	-10

For Loop Examples

Print the numbers 1 to 9

for k in range(1,10):
    print(k)

Countdown from 10 to 1

for k in range(10,0,-1):
    print(k)

Print the days of the week

for day in ["Sunday","Monday","Tuesday","Wednesday","Thursday", "Friday","Saturday"]:
    print(day)

Print the five times table

for k in range(1,11):
    print("5 x {0} = {1}".format(k, 5*k))

For Loop Exercises

Write for loops to output the following sequences of numbers

0,1,2,3,4,5,6,7,8,9,10
0,2,4,6,8,10,12,14,16
1,2,3,4,5, … 97,98,99,100
7,14,21, … 63,70,77
20,18,16, … 4,2,0,-2
2,5,8,11,14,17,20,23,26,29
99,88,77,66,55,44,33,22,11,0
Numbers 1 to 1000.
Even numbers from 0 to 100.
Odd numbers from -50 to 50
All multiples of 3 up to 500.

Extension

Use a for loop to print the 5 times table up to 12 x 5
Use a for loop to print the 7 times table up to 12 x 7 in the form “3 x 7 = 21”
Use a for loop to print the following sequence: 0.5, 0.4, 0.3, 0.2, 0.1, 0
Use a for loop to print the following sequence: 0.03, 0.02, 0.01, 0, -0.01, -0.02, -0,03
Use a for loop to print five random numbers between 1 and 10
Use a for loop to print the first ten square numbers: 1, 4, 9, 16, 25, 36, 49, 64, 81, 100
Use a for loop to print the first ten triangle numbers: 1, 3, 6, 10, 15, 21, 28, 36,45, 55

Sample Code

food = ["Sausage", "eggs", "Bacon", "Beans"]
pupils = ["John", "Jill", "Emily", "Satpal"]
scores = [5,3,6,7,9,1,2]
days = ["Sunday","Monday","Tuesday","Wednesday","Thursday", "Friday","Saturday"]
for day in days:
    print(day)
print(food[1])
print(pupils[2:])
print (days[2:4])
print(pupils[:2])
print(days[-2])
print(len(days))
print(max(scores))
print(min(scores))
if "John" in pupils:
    print("Pupil is present")
else:
    print ("Pupil absent")
pupils = pupils + ["Arthur"]
print(pupils)

Exercises

The following questions refer to the sample code. You can type the code into IDLE and run it to help you figure out the answer

Look at the print(food[1]) line. What does the [ 1] do?
How would you print the first item in the list?
If a python list has seven items, what would number would the seventh item be?
Look at the print(pupils[2:]) line. What does [2:] mean?
Look at the print(days[2:4])line. What does [2:4] mean?
Look at the print(days[-2]) line. What does [-2] mean?
What does len do?
What do max and min do?

Now write your own modules to do the following

Create a list called months, containing the months in the year.
Print out all the months, one after the other
Use slicing (e.g. days[2:4}) to print out the spring months: March, April, May
Print out the summer months: June, July, August
Print out the first and last months of the year
Print out the winter months: December, January and February

Research

Use a search engine and online manuals to find out how to get Python to do the following

Reverse the following list: [“Sunday”,”Monday”,”Tuesday”,”Wednesday”,”Thursday”, “Friday”,”Saturday”] i.e. print out “Saturday”,”Friday”,”Thursday”,… etc
Remove “eggs” from this list food = [“Sausage”, “eggs”, “Bacon”, “Beans”]
Sort the following list into ascending order scores = [5,3,6,7,9,1,2]
Insert “Mushrooms” into this list, just after “eggs”
Count how many times “blue” appears in this list [“red”,”blue”,”blue”,”blue”,”red”,”blue”]

Sample Code

Simple Selection

surname = input("Enter your surname\n")
gender = input("Are you M or F?\n")
if gender == "M":
    print("Hello Mr " + surname)
else:
    print("Hello Ms " + surname)

Operators

day = input("Name a day that starts with the letter S\n")
if day == "Saturday" or day == "Sunday":
    print("Correct")
else:
    print("Wrong")

year = int(input("Input your year\n"))
if year>=7 and year <=9:
    print("You are in KS3")
else:
    print("You are not in KS3")

Exercises

Prompt the user as follows: “What’s the capital of France?” Output “Correct” if they enter “Paris”, output “Incorrect” otherwise
Prompt the user as follows: “Name a month that starts with the letter A”: Output “Correct” if they enter “April” or “August”, output “Incorrect” otherwise
Prompt the user as follows: “Name a Beatle”. Output “Correct” if they enter “John”, “Paul”, “George” or “Ringo”, output “Incorrect” otherwise
Prompt the user to enter their age. If they are 18 or over output “You are old enough to vote.” Otherwise, output “You are too young to vote”
Prompt the user to enter their age. If they are aged between 4 and 16 output “You should be at school”
An online whisky shop charges for shipping as follows: One bottle, £5.99; two to five bottles, books £7; more than five bottles, free. Prompt the user to enter the number of bottles bought and output the shipping cost.
An online bookshop charges shipping as follows: Orders less than £10, £2.99; orders £10 and over, free; add on £2.50 for all orders if next day delivery is selected. Prompt the user to enter the cost of the order, and then prompt for next day delivery. Output the shipping cost.

Extension

The modulo operator (%) is very useful. It works out the remainder when one number is divided by another. So

10 % 2 = 0 (Because 10/2 = 5 remainder 0)

10 % 3 = 1 (Because 10/3 = 3 remainder 1)

Use the modulo operator to solve the following problems.

Prompt the user to enter a number. Output if the number is odd or even.
Prompt the user to enter a humber. Output Fizz if the number is divisible by 3, otherwise just output the number
Extend the above problem so that the computer will output Fizz if the number is divisible by 3, output Buzz if the number is divisible by 5 and otherwise just output the number.
Now extend the above problem again so that the computer will output Fizz if the number is divisible by 3, output Buzz if the number is divisible by 5, output Fizz Buzz if the number is divisible by both 5 and 3 and otherwise just output the number.

1 – Input and Output (Level 3)

Sample Code

Escape Characters

Escape Sequence	Character
\n	newline
\t	tab
\b	backspace
\”	double quote
\’	single quote
\\	backslash
\uDDDD	Unicode character

print("\u0041")

Simple Input

name = input('Enter your name: ')
print('Hello', name)

Format Output

pounds = 2
exchange = 1.38
print("{0} Pounds = {1} Euros".format(pounds, exchange))

Exercise

Use the \t escape character to print out a noughts and crosses grid, as shown below in fig. 1
Prompt the user to enter their (name). Print out “Hello” (name) “I hope you’re well”
Prompt the user to enter their (name) and their (age). Print out (name) ” is ” (age) “years old.”
Prompt the user to enter two numbers. Print out the sum of those numbers.
Prompt the user to enter two numbers. Print out the average of those numbers.
Prompt the user to enter their name and their age. Print out “Hello” (name) “you are” age “years old.”
Get the computer to tell a Knock Knock Joke. “Knock Knock” (wait for input) “Olivia” (wait for input) “No you don’t, I live here”
Print the dandelion shown in fig. 2

Table 1: fig. 1
o		x
	x	o
o	x	o

fig. 2

      .--.
    .'_\/_'.
    '. /\ .'
      "||"
       || /\
    /\ ||//\)
   (/\\||/
______\||/_______

Extension

Look up the current pounds to dollars exchange rate. Write a program that prompts the user to input a number of pounds and then outputs how many dollars that is.
To work out your BMI, divide your weight in kilograms by your height in metres squared. In other words BMI = w / h*h. Write a program that prompts the user to input their weight and height, and then outputs their BMI.

Python Levels

The Daily Python questions are levelled as follows. It’s my experience that nearly all students are capable of coding at level 3. Some students need help to progress to subsequent levels.

The following are based on my department’s experience in teaching coding. You may disagree with the levels, you may wish to use them as a starting point for further development, either way, I’d be very interested to hear your opinion.

The level numbers start at 3 to fit in with the old KS3 levelling system.

Level 3

Output Strings and numbers
Concatenate Strings and numbers
Use variables
Perform simple arithmetic operations
Prompt for user input

Level 4

Use if statements with Strings
Use if statements with numbers
Use if else statements
Understand difference between addition and concatenation.

Level 5

Elif
For loops
A list
Concise Comments

Level 6

Boolean operators AND OR NOT
Counts and iterations while loops
Nest if statements
Functions and parameters

Level 7

Nest for, while loops
2D Arrays
Scope

Level 8

Recursion
Modular programming
Self-documenting code: high level commenting

Tag Archives: Python

Functions and Parameters (Level 6)

Sample Code

Exercises

Extension

Data Types: int and float (Level 3)

Examples

Exercise

Extension: Fahrenheit to Celsius

Test data

4 – For Loops (Level 5)

For Loop Examples

For Loop Exercises

Extension

3 – Python Lists (Level 5)

Sample Code

Exercises

Research

2 – Selection (Level 4)

Sample Code

Simple Selection

Operators

Exercises

Extension

1 – Input and Output (Level 3)

Sample Code

Escape Characters

Simple Input

Format Output

Exercise

Extension

Python Levels

Level 3

Level 4

Level 5

Level 6

Level 7

Level 8