Python - Unary Operator Overloading

Unary operators are those operators which acts upon a single operand to produce a new value. Following is the list of unary operators and corresponding magic methods that can be overloaded in Python.

The unary operators is used with object in the same way as it is used normally. The operator normally precedes object in the expression like - +obj, -obj, and ~obj.

Example: overloading unary minus (-) operator

In the example below, unary minus operator is overloaded. When it is used with vector object, it applies negation on x and y component of the object, for example - applying negation on (10, 15) will produce (-10, -15) and applying negation on (5, -25) will produce (-5, 25).

class vector:
  def __init__(self, x, y):
    self.x = x
    self.y = y
  def __str__(self):
    return "({0},{1})".format(self.x, self.y)
  
  #function for operator overloading
  def __neg__(self):
    X = -self.x
    Y = -self.y
    return vector(X, Y)

#creating vector objects
v1 = vector(10, 15)
v2 = vector(5, -25)

#using overloaded unary - operator 
#with vector objects
v1 = -v1
v2 = -v2

#displaying the result
print("v1 =", v1)
print("v2 =", v2)

The output of the above code will be:

v1 = (-10,-15)
v2 = (-5,25)