Variables are containers for storing data values.
Python has no command for declaring a variable.
A variable is created the moment you first assign a value to it.
x = 5 y = "John" print(x) print(y)
Variables do not need to be declared with any particular type, and can even change type after they have been set.
x = 4 # x is of type int x = "Sally" # x is now of type str print(x)
If you want to specify the data type of a variable, this can be done with casting.
x = str(3) # x will be '3' y = int(3) # y will be 3 z = float(3) # z will be 3.0
Get the Type
You can get the data type of a variable with the type() function.
x = 5 y = "John" print(type(x)) print(type(y))
Single or Double Quotes?
String variables can be declared either by using single or double quotes:
x = "John" # is the same as x = 'John'
Variable names are case-sensitive.
This will create two variables:
a = 4 A = "Sally" #A will not overwrite a
Python is not “statically typed”. We do not need to declare variables before using them or declare their type. A variable is created the moment we first assign a value to it. A variable is a name given to a memory location. It is the basic unit of storage in a program.
Let’s see the simple variable creation:
#!/usr / bin / python # An integer assignment age =45 # A floating point salary =1456.8 # A string name ="John" print(age) print(salary) print(name)
45 1456.8 John
Let’s see how to declare the variable and print the variable.
# declaring the var Number =100 # display print( Number)
We can re-declare the python variable once we have declared the variable already.
# declaring the var Number =100 # display print("Before declare: ", Number) # re-declare the var Number =120.3 print("After re-declare:", Number)
Before declare: 100 After re-declare: 120.3
Also, Python allows assigning a single value to several variables simultaneously with “=” operators. For example:
#!/usr / bin / python a =b =c =10 print(a) print(b) print(c)
10 10 10
Python allows adding different values in a single line with “,”operators.
#!/usr / bin / python a, b, c =1, 20.2, "GeeksforGeeks" print(a) print(b) print(c)
For more, checkout W3Schools and Geeks For Geeks.