Python Lambda
A lambda function is a small anonymous function.
A lambda function can take any number of arguments, but can only have one expression.
Syntax
lambda arguments : expression
The expression is executed and the result is returned.
A lambda function that adds 10 to the number passed in as an argument, and print the result:
x = lambda a : a + 10
print(x(5))
Lambda functions can take any number of arguments.
A lambda function that multiplies argument a with argument b and print the result:
x = lambda a, b : a * b
print(x(5, 6))
A lambda function that sums argument a, b, and c and print the result:
x = lambda a, b, c : a + b + c
print(x(5, 6, 2))
Why Use Lambda Functions?
The power of lambda is better shown when you use them as an anonymous function inside another function.
Say you have a function definition that takes one argument, and that argument will be multiplied with an unknown number:
def myfunc(n):
return lambda a : a * n
Use that function definition to make a function that always doubles the number you send in:
def myfunc(n):
return lambda a : a * n
mydoubler = myfunc(2)
print(mydoubler(11))
Or, use the same function definition to make a function that always triples the number you send in:
def myfunc(n):
return lambda a : a * n
mytripler = myfunc(3)
print(mytripler(11))
Or, use the same function definition to make both functions, in the same program:
def myfunc(n):
return lambda a : a * n
mydoubler = myfunc(2)
mytripler = myfunc(3)
print(mydoubler(11))
print(mytripler(11))
Comments
0 comments
Article is closed for comments.