data types

the four core data types

int

float

string

bool

Other data types

The above types are the most commonly encountered. However, most modern programming languages require other types.

None

Yes, we need a type for when nothing exists. 

None is a special constant in Python that represents the absence of a value or a null value. It is an object of its own datatype, the NoneType.

You can use None as a placeholder for an object that you don't want to instantiate yet, or as a default value for a function argument that has no default value specified.

x = None

if x:

  print("x is not True")

elif x is False:

  print ("x is not False")

else:

  print("None is not True, or False, None is just None...")

Complex

In Python, the complex type represents complex numbers, which are numbers with a real and imaginary component. A complex number has the form a + bj, where a is the real component and b is the imaginary component, and j is the imaginary unit.

# Using the complex function

z1 = complex(3, 4)  # 3 + 4j

z2 = complex(1, -2)  # 1 - 2j

# Using the j notation

z3 = 3 + 4j

z4 = 1 - 2j

Collections

There are other types too, the most common are the list and the dict (short for dictionary).

These are collections of all of the above types and more.

the 4 built int data types are:

1. list 

2. tuple 

3. set 

4. dict

List

In Python, a list is a collection of items that are ordered and changeable. Lists are written with square brackets, and the items are separated by commas.

# Create a list of integers

numbers = [1, 2, 3, 4, 5]

# Create a list of strings

names = ['Alice', 'Bob', 'Charlie']

# Create a list of mixed data types

mixed = [1, 'Alice', 2.5, True]

Dict

In Python, a dictionary is a collection of items that are stored as key-value pairs. Dictionaries are written with curly braces, and the items are separated by commas. The keys are used to access the values, and they must be unique within a dictionary.

# Create a dictionary with string keys and integer values

ages = {'Alice': 25, 'Bob': 30, 'Charlie': 35}

# Create a dictionary with integer keys and string values

colors = {1: 'red', 2: 'green', 3: 'blue'}

# Create a dictionary with mixed data types

mixed = {'Alice': 25, 1: 'one', 2.5: [1, 2, 3]}

Objects