Python Data Types

Question 1

What are the 3 Python numbers?

Give examples

Answer 1

Integers, floating point numbers and complex numbers fall under Python numbers category. They are defined as int, float and complex classes in Python.

We can use the type() function to know which class a variable or a value belongs to. Similarly, the isinstance() function is used to check if an object belongs to a particular class.

a = 5
print(a, “is of type”, type(a))

a = 2.0
print(a, “is of type”, type(a))

a = 1+2j
print(a, “is complex number?”, isinstance(1+2j,complex))

OUTPUT

5 is of type
2.0 is of type
(1+2j) is complex number? True

Question 2

What are the 3 sequence data types?

Answer 2

List, tuple, range

Question 3

What are the mapping data types?

Answer 3

Dict

Question 4

What is a List?

Give examples

Answer 4

a list is an ordered sequence of items.

Declaring a list:
a = [1, 2.2, ‘python’]

A list is mutable.

Question 5

What is a Tuple?

Give examples

Answer 5

A Tuple is an ordered sequence of items but they are immutable.

Declaring a tuple:
t = (5, ‘program’, 1+3j)

Question 6

What is a String?

Give examples

Answer 6

A string is a sequence of unicode characters.

s = “this is a string”

print (s)

Question 7

How do you use a slicing operator to extract an item from a List?

Give examples

Answer 7

a = [5, 10, 15, 20, 25, 30, 35, 40]

# a[2] = 15
print("a[2] = ", a[2])

# a[0:3] = [5, 10, 15]
print("a[0:3] = ", a[0:3])

# a[5:] = [30, 35, 40]
print("a[5:] = ", a[5:])

Question 8

What is a Dictionary?

Give examples

Answer 8

is an unordered collection of key - value pairs. It is generally used for large datasets.

Dictionaires have a key:value and can be of any type.

d = {1: ‘value’, ‘key’: 2}
print (type(d))

print (“d[1] = “, d[1]);

print (“d[‘key’]”, d[key]);

OUTPUT

d[1] =  value
d['key'] =  2