Python Data Types

Question 1

Numeric Types

Answer 1

Int, Float, Complex

Question 2

Int

Answer 2

Ints are considered a primitive scalar type

Ints allow for unlimited precision (as many digits as you need)

Integers are always rounded towards zero
int(3.9) = 3
int(-3.9)=-3

Question 3

float

Answer 3

float = floating point number

any number containing a decimal is interpreted as a float in python

Question 4

None

Answer 4

None = null object (represents the absence of a value)

We can assign a value as None using the assignment operator: a = None

We can test if something is None using the “is” operator
a is none // True

Question 5

bool

Answer 5

bool = boolean objects (True / False)

represents logical states and play an important role in Python control flow structures

Question 6

str

Answer 6

str = string

this is a collection type

strings are sequences of chars

strings are IMMUTABLE meaning once you have constructed a string, you cannot modify its contents

Question 7

tuple

Answer 7

( )

a tuple is a collection

a tuple is:
- ordered
- immutable (we cannot add or remove items)
- allows duplicates

similar syntax to lists, but they use parentheses

Question 8

set

Answer 8

{ }

A set is a collection

sets are
- unordered
- unindexed
- mutable
- no duplicates

items within a set are unchangeable, but you can remove items and add new ones

A common use for a set is to remove duplicate items from a series of objects

Question 9

list

Answer 9

[ ]

A list is a collection

Lists are:
- ordered
- mutable
- allow duplicate values
- indexed

Question 10

range

Answer 10

range = a sequence representing an arithmetic progression of integers, generated by calls to the range constructor

range determines what it’s arguments mean by counting them

one arg = range(stop)
two arg = range(start, stop)
three args = range(start, stop, step)

Question 11

dict

Answer 11

{ }

dicts are a mapping type

store values as key-value pairs

• iterable
• keys are immutable, unique (strings, numbers, tuples)
• values are mutable

as of Python 3.7, dicts are ordered

Question 12

Primitive

Question 13

Non-Primitive

Question 14

Immutable

Question 15

Sequence

Answer 15

Type of Collection (there are three: sequence, set, mapping)

Ordered
It’s elements can be accessed using a numeric index

examples: lists, tuples, ranges

Question 16

Mapping

Answer 16

Type of Collection (there are three: sequence, set, mapping)

stores data in key-value pairs

ordered

example: dict

Question 17

Set

Answer 17

{ }

Type of Collection (there are three: sequence, set, mapping)

• Unordered
• Immutable
• comprised of unique objects

Question 18

Collection

Answer 18

A collection is an object that has zero or more member objects, called elements

Categories of collections:
1. sequences (list, tuple, range)
2. mappings (dict)
3. sets (set, frozenset)

Question 19

Text Sequence

Answer 19

Strings and other text sequences are not considered collections

however, they are very similar to sequence collections

example: str

Question 20

Literal

Answer 20

A literal is a syntactic notation that lets you directly represent an object in source code

they are constants that are directly written into the code and don’t need to be computed or evaluated

You can use literals to represent most data type values

Question 21

Numeric

Answer 21

Numeric values represent numbers

integers and floats are both numeric values