Function Arguments
Arbitary Arguments
Arbitary arguments are shortened as *args in python documentation.
If we are not sure on number of arguments that will be passed into our function, then we use * sign before the parameter name while defining the function.
If the number of arguments is unknown, just add * before the parameter name. In this manner, the function accepts the tuple of elements as arguments and access the elements accordingly.
Example
def myfun(*args):
for item in args:
print(item)
myfun(40,60,40,50,60,70)
Example
def myfunc(*args):
mylist = []
for item in args:
if item%2 == 0:
mylist.append(item)
return mylist
myfunc(5,6,7,8)
keyword Arguments
We can also send the arguments as key = value pair.
In this case, the order of the arguments does not matter.
Example
def my_function(child3, child2, child1):
print("The youngest child is " + child3)
my_function(child1 = "Emil", child2 = "Tobias", child3 = "Linus")
Arbitary Keyword Arguments
Arbitary Keyword Arguments are shortened as **kwargs in python documentation.
If we are not sure on number of keyword arguments that will be passed into our function, then we use ** sign before the parameter name while defining the function.
In this manner, function will accept dictionary items and can access elements accordingly.
Example
def myfunc(**kwargs):
print(kwargs)
if 'fruit' in kwargs:
print('my fruit of choice is {}'.format(kwargs['fruit']))
else:
print('I did not find any fruit here')
myfunc(fruit='apple', veggie='lettuce')
Example
def myfunc(*args, **kwargs):
print('I would like {} {}'.format(args[0], kwargs['food']))
myfunc(10,20,30,fruit='orange', food='eggs', animal='dog')
Passing a List as an argument.
We can pass any type of data as argument to a function, that will be treated as same data type inside the function.
Example
def my_function(food):
for x in food:
print(x)
fruits = ["apple", "banana", "cherry"]
my_function(fruits)
Recursion
Recursion of function indicates calling function by itself.
Example
def recursion_fun(k):
if(k > 0):
result = k + recursion_fun(k - 1)
print(result)
else:
result = 0
return result
print("\n\nRecursion Example Results")
recursion_fun(2)
In this case, recursion_fun is a function that is defined to call itself. Here, K value decrements by -1 everytime and recursion stops when the k value is not greater than 0.
In the above example, the operation will be as follows
recusrion_fun
whenk=2
result = 2 + rescursion_fun(1)
This will wait for the result ofrecursion_fun(1)
, oncerecursion_fun(1)
returns a result, that will be added to 2 and total result will be printed.recursion_fun
whenk=1
result = 1 + recusrion_fun(0)
recursion_fun(0)
result will be returned as 0 and this won't be printed as there is no print result in else part.
result of therecusrion_fun(1)
will be printed as 1 (1+0) and result will be returned.
Now, the result ofrecursion_fun(2)
will be 3 (2+1) and this will result be printed and returned to the function.