The Underscore (_) is an eccentric character in Python. It can be used in many ways in a Python program.
The various uses of underscore (_) in Python are:
1) Use in Interpreter:
Python immediately saves the value of the last expression in the interpreter in this unique variable. Underscore (_) can also be used to value of any other variable.
Example 1:
Underscore (_) can be also be used as a normal variable.
Example 2:
Python3
# Storing value in __ = 2 + 8print(_) |
Output:
10
2) Use in Loops:
In Python underscore (_) can be used as a variable in looping. It will access each element of the data structure.
Example 1:
Python3
# Creating tupleTuple = (50, 40, 30)# Using _ to access index of each elementfor _ in range(3): print(Tuple[_]) |
Output:
50 40 30
Example 2:
Python3
# Creating listList = ['Geeks', 4, 'Geeks!']# Using _ to access elements of listfor _ in List: print(_) |
Output:
Geeks 4 Geeks!
3) Use in Ignoring Variables:
In Python underscore (_) is often used to ignore a value. If one doesn’t use some values when unpacking, just set the value to underscore (_). Ignoring involves assigning values to a particular vector underscore (_). We add values to underscore (_) if this is not used in future code.
Example 1:
Python3
# Using _ to ignore valuesp, _, r = 'Geeks', 4, 'Geeks!'print(p, r) |
Output:
Geeks Geeks!
Example 2:
Python3
# Using _ to ignore multiple valuesp, q, *_, r = 'Geeks', 4, 'randomText', 1234, '3.14', "Geeks!"print(p, q, r)print(_) |
Output:
Geeks 4 Geeks! ['randomText', 1234, '3.14']
4) Separating digit of Numbers:
Underscores (_) can also be used to represent long digits number, it separates the group of digits for better understanding.
Python3
# Using _ to separate digitsCrore = 10_00_000print(Crore) |
Output:
1000000
5) Use in Defining Access of Data members and Methods in Class:
Underscore (_) is used as a prefix for a method or data member in a class, defines its Access Specifier, and using double underscores (__) as both suffix and prefix refer to a Constructor.
Example 1:
Python3
class Gfg: a = None _b = None __c = None # Constructor def __init__(self, a, b, c): # Data members # Public self.a = a # Protected self._b = b # Private self.__c = c # Methods # Private method def __display(self): print(self.a) print(self._b) print(self.__c) # Public method def accessPrivateMethod(self): self.__display()# Driver code# Creating objectObj = Gfg('Geeks', 4, "Geeks!")# Calling methodObj.accessPrivateMethod() |
Output:
Geeks 4 Geeks!
