2.2 Common boolean operators + data types and casting

Question 1

Types of Boolean operators

Answer 1

Types of Boolean operators

NOT

AND

OR

Question 2

What does not do

Answer 2

Reverse the result, returns False if the result is true

Question 3

Show an example where the NOT operator is used

Answer 3

while not end_of_file
This is the same as…
while end_of_file == False:

Question 4

What are boolean operators used in

Answer 4

Boolean operators are used in what are called Boolean expressions.

Question 5

Where can boolean operators be seen

Answer 5

Boolean expressions can be seen in, “if statements”, “while loops” and “ do …until loops”.

“If loop” - If a Boolean expression is true, then run some code

“While loop” - While this Boolean expression is true, run some code

“Do…until loop” - Do the following code, until this Boolean expression is true.

see relevant notebook file

Question 6

Why are Boolean expressions called Boolean Expressions

Answer 6

These expressions are called Boolean expressions because that expression equates or evaluates to either true or false.

And also in them, we can use the Boolean operators

Question 7

Give an example where it would be more beneficial if a particular data type was used instead of the other

Answer 7

There is little point in storing the whole number 22 in a real (float) data type, when the integer data type is perfectly capable of storing it and (the integer data type) takes up much less memory.

Question 8

What are the types of data types that variables and constants can hold

Answer 8

Variables and constants can hold:
Integer
Real (Float)
Character
String
Boolean

Question 9

Define Boolean

Answer 9

Boolean – True or False, often called a “flag”.

Question 10

When is the Boolean data type used

Answer 10

Boolean is used to track if something has happened or not

Question 11

When should the Integer data type be used

Answer 11

The integer data type should only be used for data that requires calculations

Question 12

When should the Real data type be used

Answer 12

Real - Only use for data that requires calculations

Question 13

When should the String data type be used

Answer 13

String - Use for all data that is not calculated

Question 14

Why is casing necessary

Answer 14

Casting is necessary so that sub-problems receive data in a format they are expecting

Question 15

State some of things casting allows for/does

Answer 15

Casting allows numbers to be manipulated as strings

Casting allows inputs that are always strings to become numbers,

X=str(X) casts the variable x to a string

X = int(X) casts the variable x to an integer

Question 16

Select the most appropiate data types needed for the variables in this scenario

“A program is to be written which asks for a user’s name, age and telephone number. If they are aged 17 or under it informs them they are not eligible as they are too young. If they are 18 or over it stores their details and tells them they are eligible to vote”

Answer 16

Step 1: Study the scenario and work out all the variable that you would need.

key info:
name, age, telephone number, not eligible to vote, are eligible to ote