Difference between revisions of "Python"

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(Variables)
(Declaration and typing)
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# Initializing an empty set:
 
# Initializing an empty set:
 
a = set()
 
a = set()
 +
####
  
 
####
 
####
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####
 
####
# Dictionaries
+
# Dictionaries work of Key - Value pairs
####
+
# Keys can be any immutable type - integers, floats, strings and tuples
 +
# Dictionaries do not keep the their order
 +
#     Dictionaries are annotated using the "dict" keyword
 +
a: dict = {"A": "Some string", "B": 15, "C": 9.6, "D": True}
  
 +
# Initializing an empty dictionary:
 +
a = {}
 +
####
 
</source>
 
</source>
  

Revision as of 13:55, 26 June 2019

Variables

Declaration and typing

####
# Boolean variables can only contain one of two values: True or False
#     Boolean values are annotated by using the "bool" keyword
a: bool = True
####
 
####
# Integers are variables that contain any positive or negative whole number
#     Integers are annotated using the "int" keyword
# Floats are variables that contains any positive or negative decimal
#     Floats are annotated using the "float" keyword
a: int = 15
b: int = -23
 
c: float = 6.4
d: float = -9.5
####
 
####
# Strings are variables that contain text
#     Strings are annotated using the "str" keyword
a: str = "This is a string"
b: str = 'Strings can be enclosed using single quotes'
 
# Initializing an empty string:
a = ""
####
 
####
# Lists are collections of other variables
#     Lists are annotated using the "list" keyword
a: list = ["Some string", 15, 9.6, True]
 
# Initializing an empty list:
a = []
####
 
####
# Sets are lists that cannot contain duplicate values
# They also do not keep the order of the variables
# Sets are a lot faster than lists when looking for specific values
#    Sets are annotated using the "set" keyword
a: set = {"Some string", 15, 9.6, True}
 
# Initializing an empty set:
a = set()
####
 
####
# Tuples are lists that cannot be changed after being created
# They are useful when returning multiple values from a function
#     Tuples are annotated using the "tuple" keyword
a: tuple = ("Some string", 15, 9.6, True)
 
# Because tuples cannot be changed there is no point in initializing an empty one
####
 
####
# Dictionaries work of Key - Value pairs
# Keys can be any immutable type - integers, floats, strings and tuples
# Dictionaries do not keep the their order
#     Dictionaries are annotated using the "dict" keyword
a: dict = {"A": "Some string", "B": 15, "C": 9.6, "D": True}
 
# Initializing an empty dictionary:
a = {}
####

Conditionals

Loops

Functions

Classes