Unit 5

Question 1

What is the purpose of function?

Answer 1

In order to save time and reuse code. Like many programming languages, Python doesn’t want you to type the same code over and over again.

Question 2

Is print a function?

Answer 2

Yes

Question 3

What is a function?

Answer 3

A function is a set of commands that’s been saved to be used again and again. it is a reusable block of code that you can use over again in your program without having to retype every line.

Question 4

What are the three different parts to a function?

Answer 4

First part: A name
Second part: Parameters
Third part: A body.

Question 5

What does the part of the function “name” do?

Answer 5

Just like with variables, you want to give your function a name that lets you know exactly what it does.

Question 6

What is the meaning of “def”?

Answer 6

It is the first part of the function. It is short for define, which tells Python that we’re going to start writing a function.

Question 7

What is the purpose of the “name” part of a function?

Answer 7

It tells Python that we’re going to start writing a function.

Question 8

What is the purpose of the “parameters” part of a function?

Answer 8

Parameters let you give the function, information to work with.

Question 9

Can a function have more than one parameters?

Answer 9

Yes, they are separated by commas.

Question 10

Is this statement true or false?

You can create functions with no parameters or one parameter or as many parameter as you would like.

Answer 10

True.
It just depends on how many you need to make your function work.

Question 11

What is the function of the third part of the function “body”?

Answer 11

It is to make the function do something

Question 12

What should the third part of the function “body” have?

Answer 12

Your body has to have an indentation (the extra white part) before it so that Python knows it’s part of the function definition.

Question 13

When you enter a function into the console (remembers the one with the prompt of arrows»>), IDLE will automatically ______________.

Answer 13

When you enter a function into the console (remember, the one with the prompt of arrows&raquo_space;>), IDLE will automatically ident the next line for you after your “def” line,

Question 14

How do you stop writing a function?

Answer 14

To stop writing a function, press enter twice to get the prompt (»>symbol) back.

Question 15

How do you get out of defining your function if you write a function outside of the console?

Answer 15

When you write a function outside of the console (to save and submit for an assignment for instance), IDLE will add the tab and you will need to use the backspace or delete key to stop indenting and get out of defining your function.

Question 16

What is the short cut to create a new file?

Answer 16

Control + N or command + N will create a new file.

Question 17

What is the short cut that will run your file?

Answer 17

F5 key

Question 18

We’ve learned how to send information to our function using parameters, but what if we want to receive information back from it?

Answer 18

We use the word “return” in our code for that.

Question 19

def calculate allowance (allowance_per_chore, number_of_chores): (by right should be in one line)
return allowance_per_chore * number_of_chores

What are the three ways that we can code to continue this program if let’s say you did 5 chores and each allowance per chore is $2?

Answer 19

First, we can just print out the result
print (calculate_allowance(2.5))
10

Or

The other thing we can do is assign the result to another variable.
allowance= calculate_allowance (2,5)
print(allowance)

Or

Use another variable to store our information and then use those as parameters for our function

mark_allowance_per_chore = 2
mark_number_of_chores= 5
kate_allowance_per_chore =3
kate_number_of_chores = 4
calculate_allowance (mark_allowance_per_chore , mark_number_of_chores)
Output: 10
calculate_allowance (kate_allowance_per_chore , kate_number_of_chores)

Question 20

Code this program:
To update our hours to seconds function to ask the user for input and then convert that number and return it.

Answer 20

def hours_to_seconds (hours):
print (hours * 60 *60)

Let’s update it now to ask for user input. We need to make sure that we change the entry to an integer or else our function won’t work .

def hours_to_seconds ():
hours= int(input(“Hours:”))
return hours * 60 *60

Now instead of printing out the seconds, we return the value, Let’s try using our function by printing out the results.

print (hours_to_seconds_())
Hours: 3 (user input)
10800

We successfully used our function to ask the user how many hours they would like to convert and then we returned the value in seconds and printed it out!

Question 21

Write a program that prompts the user to enter three values: product name, product price, and quantity, and store these values into appropriate variables. Calculate the total price by multiplying products price by the quantity, Print the total price with an appropriate label as displayed above.

Enter product name: notebooks
Enter price: 1.99
Enter quantity: 8
8 notebooks cost 15.92

Answer 21

Get user input

product_name = input(“Enter product name:”)
price=float(input(“Enter price:”))
quantity=int(input(“Enter quantity:”))
#Calculate total price
total_price = price * quantity
# Print out results
print(“{} {}cost {}”.format(quantity, product_name, total_price))

Question 22

Get this as output:
Enter product name: notebooks
Enter price: 1.99
Enter quantity: 8
8 notebooks cost 15.92

Extend the previous activity, this time calculating and printing the total price in formatted output using a function.
Prompt the user to enter: product name, price, and quantity, in that order.

Answer 22

Define a function to calculate and print total price

def calculate_and_print_total(name, price, qty):
#Calculate total price
total_price = price * quantity
#Print output
print(“{} {} cost {}”.format(qty, name, total_price))
#Get user input
product_name = input(“Enter product name:”)
product_price = float(input(“Enter price:”))
quantity= int(input(“Enter quantity”))
#Call the function
calculate_and_print_total(product_name, product_price, quantity)

Question 23

What do we do if we want to receive information back from a function?

Answer 23

We use the function “return”.

Question 24

Code something that get this as the output
Enter product name: notebooks
Enter a price: $1.99
Enter quantity: 8
8 notebooks cost $15.92

Extend the previous activity again, this time returning the total price from a function and print the formatted output from your main program.

Answer 24

Define a function to calculate total price

def calculate_total(price, qty):
#Calculate and return total price
return price * qty
#Get user input
product_name = input(“Enter product name:”)
product_price= float(input(“Enter a price: $”))
quantity = int(input(“Enter quantity:”))
#Call the function
total_price = calculate_total(product_price, quantity)
#Print results
print(“ {} {} cost ${}”.format(quantity, product_name , total_price))

Question 25

What is an integer?

Answer 25

integer can be any whole number such as: 1,2,300,28765, etc. However, integer was cannot hold decimal points.

Question 26

What is a float?

Answer 26

Floats can be any real number, for example: 2.75, 0.234, 100.0 etc. For decimal points, we need to use floating point numbers- also called floats.

Question 27

If you want to add an integer to a float, ____________.

Answer 27

Python automatically first converts the integer to a float and then adds it to the other floating point number. Then, the result is as a float.

Question 28

Consider the following code. What would the output be?
X= 3+ 4.0
print (“x= {}”.format(X))

Answer 28

The integer 3 is first converted to a float, 3.0, and then added to 4.0 resulting in 7.0. The value of X is 7.0. Output below: X=7.0

Question 29

You can also force conversion of one type of number to another type explicitly using the ___ and the ____ casting functions.

Answer 29

int() and float()

Question 30

Consider the following code. What would the output be?
a=3.7
b=4
c= int(a) + b
print (“c={}”.format(c))

Answer 30

First, a is cast to an integer and then its value is added to b (also an integer). The resulting value of c is an integer, 7. Note that a was not rounded up to the nearest whole number when it was cast to an integer. Instead, the decimal part was removed entirely.
output below:
c=7

Question 31

What is a string?

Answer 31

A string is when letters, numbers, spaces, symbols are enclosed by quotation marks.

Question 32

Is a string a number?

Answer 32

No

Question 33

you must explicitly convert a ________ to an integer or float using int() and float() casting functions.

Answer 33

String number

Question 34

A string is not a number. True or false?

Answer 34

true

Question 35

Consider the code below:
X= ‘3’
Y=4
Z= int(X) + Y
print(“Z = {}”.format(Z))
What would the output be? Explain.

Answer 35

First, X, the string ‘3’ is cast to an integer. Then, it’s added to the value of Y and stored in the variable Z. The resulting value of Z is then printed as shown below. Note, without a cast, Python has an error. you cannot combine/ add a string and an integer.
Output:
Z=7

Question 36

What is the definition of scope?

Answer 36

Scope refers to where we define our variables and where we can use them and not use them.
Where a variable exists, and can be used, is called its scope.

Question 37

We have used variables both __ and ____ of functions.

Answer 37

Inside and outside

Question 38

Look at the code and state what would happen if we print(variable_a)

def scope_experiment():
variable_a = 5
variable_b = 9
return variable_a + variable_b

print(scope_experiment())
Output: 14
print (variable_a)

Answer 38

You will get a NameError, saying that variable_a is not defined. That is because the variable is only defined inside the function, so you can only use it inside the function we made.

Question 39

variable_c=11
def scope_experiment_2():
variable_a= 5
variable_b = 9
return variable_a + variable_2 + variable_c

print (scope_experiment_2 ())

What would the output be and why?

Answer 39

The output would be 25. Since we declared variable_c in our main program, we can use it inside the function. (Declaring a variable outside of the function and then trying to use it inside a function.)

Question 40

You can think of the function like an octopus in a bin. It can use variables from _______ its bin and _____ its bin. But things ____ the bin can’t get to the variables _____ the bin.

Answer 40

It can use variables from outside its bin and inside its bin.
But things outside of the bin can’t get to the variables inside the bin. If you ever get a similar error, make sure you’re using a variable that’s defined inside the proper scope.

Question 41

variable_a = “boo!”
def scope_test():
variable_b = “eek!”
print (variable_a)
print(variable_b)

scope_test()
What would the output be and why?

Answer 41

Output:
boo!
eek!

When we run that code, both print statements will work correctly. variable_a can be accessed in the entire program, while variable_b only works inside the function, so both can be accessed from inside the function.

Question 42

print(variable_a)
boo!
print(variable_b)

What would the output be?

Answer 42

Output:
you will get an error. variable_b is not defined.

variable_b only works inside the function, not outside of it.

This is because we are accessing both variables from the program, not inside the function.

Question 43

Any changes that the function makes to variable_b only happen inside the function. What we put in variable_b from outside of the function stays there. (Said by the person teaching python in the video)

Variables defined in the program outside of the function can be used. Let’s say variable_a= “boo!” and variable_b = “whee!” is outside of the function and variable_b = “eek!” is inside the function, when you declare variable_b outside of the function, what would it be?

Answer 43

It would be whee

Question 44

Trace through the lines of code below. What valued are printed out for “sum” and “value”?
def add_these(x,y):
value = x+y
return value
#Main program
value = 10
sum = add_these(2,3)
print(“sum = {}”.format(sum))
print(“value= {}”.format(value))

TIP: As you trace through the code, use pencil and paper to keep track of each variable.

Answer 44

sum = 5
value = 10
Remember that the scope of “value” in. The main program keeps this value of 10 being printed out.

Question 45

Is there anything wrong with this code? If so, why?

def add(num1+ num2):
return num1+ num2
print(add(20,10))

Answer 45

Yes, this is called an indentation error. You will get a syntax error. The error is thrown because we forgot to indent the code int the body of the function add(). Indentation refers to the number of spaces (or white space) at the beginning of the code line. Python enforces indentation strictly. That means that white space matters.

Question 46

def add(num1, num2):
print(“Here is the answer”)
print(num1 + num2) #Note indentation is different than the print statement above
add(20, 10)

If you run this code, what will happen and why?

Answer 46

If you run this in Python, you’ll get the following error:

SyntaxError: unindent does not match any outer indentation level
Did you notice the extra whitespace before the first print statement? This error is thrown because there is inconsistency in the number of spaces before each line of code in the function body.

*Tip: Remember to use whitespace to indent before every line of code in the function body, and be consistent with the number of spaces.

Question 47

print(add(20, 10))
def add(num1, num2):
return num1 + num2

What will happen when you run this program and why?

Answer 47

When run the program above, we get the following error:

Traceback (most recent call last):
File “C:/Users/96C32572223744/Desktop/test.py”, line 1, in <module>
print(add(20, 10))
NameError: name 'add' is not defined
Python can't find the add() function and will throw the NameError: name 'add' is not defined because it's being called before it was ever defined in the program.</module>

This is a very common error: calling a function before defining it.

The correct way to write the code is by first defining the function, and then calling it, as shown below:

def add(num1, num2):
return num1 + num2
print(add(20, 10))
*TIP: Remember to always define a function before calling it.

Question 48

def add(num1, num2)
return num1 + num2
print(add(10, 20))

What will happen when you run this program and why?

Answer 48

Try running this program in IDLE and what happens? You get a SyntaxError: invalid syntax. Python requires a colon (:) at the end of a function definition.

Forgetting the colon at the end of the function definition is a common mistake.

Here’s how to fix it:

def add(num1, num2):
return num1 + num2
print(add(10, 20))
*Tip: Remember to always include a colon at the end of the function name definition.

Question 49

def add(num1, num2):
return num1 + num2
print(add(“20”, 10))

What will happen when you run this code and why?

Answer 49

When we run the code, we get the following error:

Traceback (most recent call last):
File “C:/Users/96C32572223744/Desktop/test.py”, line 3, in <module>
print(add("20", 10))
File "C:/Users/96C32572223744/Desktop/test.py", line 2, in add
return num1 + num2
TypeError: can only concatenate str (not "int") to str
What does this error mean? A TypeError was thrown because the function add() is expecting a number but a string was passed as one of the arguments. When Python tried to add "20" + 10, the type error occurred because you can't add an integer to a string.</module>

Remember that parameters are the variables listed in the function name when defining it. Arguments are the values that you pass into a function when calling it. Passing mismatched or incorrect arguments when calling a function is a common mistake.

Question 50

def add(num1, num2):
return num1 + num2
print(add(10))

What will happen when you run this code and why?

Answer 50

Executing the code gives the following error:

Traceback (most recent call last):
File “C:/Users/96C32572223744/Desktop/test.py”, line 3, in <module>
print(add(10))
TypeError: add() missing 1 required positional argument: 'num2'
As the error suggests, we forgot to include the second argument when calling the function. To fix this, we need to call add() with exactly two numeric arguments:</module>

print(add(10, 20))
*TIP: When calling a function, remember to pass the correct number and type of arguments.

This is a variation of mismatched arguments: when the wrong number of arguments are given

Question 51

def add():
num1 = 2
num2 = 5
result = num1 + num2
return result
add()
print(result)

What will happen when you run this and why?

Answer 51

Python throws an error if we try to access a local variable outside the scope of the function. Remember that scope refers to where a variable can be seen and used in the program.

When we run this program, we will get the following error:

Traceback (most recent call last):
File “C:/Users/96C32572223744/Desktop/test.py”, line 8, in <module>
print(result)
NameError: name 'result' is not defined
Let's look at what's happening here. The NameError is thrown because the variable ‘result’ is local and accessible online inside of the function add() and we are trying to access it outside the function. In Python, when a variable is created inside a function, it is treated as a local variable.</module>

*TIP: Remember that all variables created inside of a function are local to only that function and cannot be accessed anywhere outside of the function.

Question 52

What is the output of the following code snippet?

def add_total (price, qty):
unit_price = 0
quantity = 0
total = 0
price = unit_price
qty = quantity
total = price * qty
return total

item_value = 10
number_of_items = 5

print (“Total is {}”.format(add_total(item_value, number_of_items)))
Question 1Select one:

a.
An error message is displayed.

b.
Total is 0

c.
Total is 50

d.
Total is 105

Answer 52

B

Question 53

True or False: The function add_numbers contains a return statement

def add_numbers (variable_a, variable_n):
print(variable_a + variable_b)
Question 2
Select one:
True
False

Answer 53

False

Question 54

Considering the following code snippet, num1 and num2 are called ________ and value1 and value2 are called _________.

def add_numbers(num1, num2):
    return num1 + num2
    
value1 = 8
value2 = 5
    
print(add_numbers(value1, value2)) Question 3Select one:

a.
arguments, arguments

b.
arguments, parameters

c.
parameters, parameters

d.
parameters, arguments

Answer 54

d

Question 55

Fill in the blank with the correct line of code:

def convert_to_meter(feet):
meter = feet * 0.3048
return meter

ft = 9
_______ #Fill in the blank here
print(“{} feet = {} meters”.format(ft, mt))
Question 4Select one:

a.
mt = convert_to_meter(ft)

b.
ft = convert_to_meter(mt)

c.
mt = return meter

d.
mt = {} meter

Answer 55

a

Question 56

Which of the following is true about functions?

Question 5Select one:

a.
Functions use indentation just like other Python code.

b.
Functions are the only way to “recycle” code in Python.

c.
Functions must be defined in a separate Python file.

d.
Functions can be defined with an empty body.

Answer 56

a

Question 57

Which keyword is used to indicate the beginning of a function?

Question 6Answer

a.
define

b.
function

c.
func

d.
def

Answer 57

d

Question 58

What are the three parts of a function?

*Choose all that apply.

Question 7Select one or more:

a.
the name

b.
the assignment operator

c.
string literal

d.
the parameters

e.
the body

f.
arguments

g.
constructor

Answer 58

a, d and e

Question 59

We define a function as…

*Choose all that apply.

Question 8Select one or more:

a.
set of commands that we can reuse.

b.
variable that we use multiple times.

c.
set of statements to do a specific task.

d.
set of modules.

Answer 59

a and c.

Question 60

Fill in the blanks in the following program.

def _________ (first_name, last_name):
_________ first_name + ‘ ‘ + last_name

first_name = input(“Enter first name: “)
last_name = input(“Enter last name: “)
full_name = full_name(first_name, last_name)
print(full_name)
Question 9Select one:

a.
return, full_name

b.
first_name, return

c.
full_name, return

d.
full_name, print

Answer 60

c

Question 61

True or False: A function can have zero parameters.

Question 10Select one:
True
False

Answer 61

True