[Basic Grammar] Python Lambda

A lambda function is small anonymous function. 

 

• Syntax 

lambda arguments : expression

Example

Add 10 to argument a, and return the result.

x = lambda a : a + 10 
print (x(8))

 

Multiply argument a with argument b and return the result. 

x = lambda a,b : a * b
print (x(8, 1))

 

Example

 

def myfunc(n):
  return lambda a : a * n

mydoubler = myfunc(2)
mytripler = myfunc(3)

print(mydoubler(11))
print(mytripler(11))

 

Exercises 

Write a Python program that defines a lambda function multiply_by which takes a number n as an argument and returns a new lambda function. The new lambda function should take another number x as an argument and return the result of multiplying n by x. Then, use this lambda function to calculate the product of 5 and 7.

def multiply_by(n): 
	return lambda a : a * n
triple = multiply_by (3)

result = triple (5) 

print ("Result:", result)

Result: 15