How do I create a Python function with optional arguments? How do I create a Python function with optional arguments? python python

How do I create a Python function with optional arguments?


Just use the *args parameter, which allows you to pass as many arguments as you want after your a,b,c. You would have to add some logic to map args->c,d,e,f but its a "way" of overloading.

def myfunc(a,b, *args, **kwargs):   for ar in args:      print armyfunc(a,b,c,d,e,f)

And it will print values of c,d,e,f


Similarly you could use the kwargs argument and then you could name your parameters.

def myfunc(a,b, *args, **kwargs):      c = kwargs.get('c', None)      d = kwargs.get('d', None)      #etcmyfunc(a,b, c='nick', d='dog', ...)

And then kwargs would have a dictionary of all the parameters that are key valued after a,b


Try calling it like: obj.some_function( '1', 2, '3', g="foo", h="bar" ). After the required positional arguments, you can specify specific optional arguments by name.


It is very easy just do this

def foo(a = None):       print(a)

Instead of None you can type anything that should be in place if there was no argument for example if you will not write value of the parameter like this foo() then it will print None because no argument is given and if you will GIVE it a argument like foo("hello world") then it will print hello world, OH YES i forgot to tell y'all that when these types of paramters i.e optional parameters, THESE ARGUMENTS NEEDS TO FOLLOW THE DEFAULT ARGUMENTS this means that, lets take the previous function and add another parameter b

def foo(a = None, b):     print(a)

Now if you'll execute your python file it is going to raise an exception saying that Non-default arguments follows default arguments,

SyntaxError: non-default argument follows default argument

so you gotta put the optional or non-default argument after the arguments which are required

which means

def foo (a, b=None): ... #This one is right(these threee dots are ellipsis which are somewhat like passdef foo(b=None, a): ... #and this isn't