Argument and parameter in python

Parameter vs Argument Python

Solution 3: In Programming lingo, arguments refers to the data you are passing to the function that is being called whereas the parameter is the name of the data and we use the parameter inside the function to refer it and do things with it. The only thing you would need to do is add one in , and you would not need to add a parameter to every function that is calling , (as long as that functions has ).

Parameter vs Argument Python

So I’m still pretty new to Python and I am still confused about using a parameter vs an argument. For example, how would I write a function that accepts a string as an argument?

Generally when people say parameter/argument they mean the same thing, but the main difference between them is that the parameter is what is declared in the function, while an argument is what is passed through when calling the function.

def add(a, b): return a+b add(5, 4) 

Here, the parameters are a and b , and the arguments being passed through are 5 and 4 .

Since Python is a dynamically typed language, we do not need to declare the types of the parameters when declaring a function (unlike in other languages such as C). Thus, we can not control what exact type is passed through as an argument to the function. For example, in the above function, we could do add(«hello», «hi») .

This is where functions such as isinstance() are helpful because they can Determine the type of an object. For example, if you do isinstance(«hello», int) , it will return False since «hello» is a string.

What is the difference between arguments and parameters?

Parameters are defined by the names that appear in a function definition, whereas arguments are the values actually passed to a function when calling it. Parameters define what types of arguments a function can accept. For example, given the function definition:

def func(foo, bar=None, **kwargs): pass 

foo , bar and kwargs are parameters of func . However, when calling func , for example:

func(42, bar=314, extra=somevar) 

the values 42 , 314 , and somevar are arguments.

• language-agnostic What’s the difference between an argument and a parameter?
  • This answer is my favourite.

  For defining a function that accepts a string, see TerryA’s answer. I just want to mention that you can add type hints to help people using your function to tell what types it accepts, as well as what type it returns.

  def greeting(name: str) -> str: return 'Hello ' + name 

  In Programming lingo, arguments refers to the data you are passing to the function that is being called whereas the parameter is the name of the data and we use the parameter inside the function to refer it and do things with it.

  def functionname(something): do some stuff with functionname(abc) 

  A parameter is the placeholder; an argument is what holds the place.

  Parameters are conceptual; arguments are actual.

  Parameters are the function-call signatures defined at compile-time; Arguments are the values passed at run-time.

  Mnemonic: «Pee» for Placeholder Parameters, «Aeigh» for Actual Arguments.

  *args and **kwargs in Python, Example 1: Here, we are passing *args and **kwargs as an argument in the myFun function. By passing *args to myFun simply means that we pass …

  How do Arguments and Parameters Work in Python?

  I have looked all over Stackoverflow and I can’t find an answer, and all the web tutorials just go right over my head. I have a functioning code that I don’t understand

  import random import time def displayIntro(): print('You are in a land full of dragons. In front of you,') print('you see two caves. In one cave, the dragon is friendly') print('and will share his treasure with you. The other dragon') print('is greedy nd hungry, and will eat you on sight.') print() def chooseCave(): cave = '' while cave != '1' and cave != '2': print('Which cave will you go into? (1 or 2)') cave = input() return cave def checkCave(chosenCave): print('You approach the cave. ') time.sleep(2) print('It is dark and spooky. ') time.sleep(2) print('A large dragon jumps out in front of you! He opens his jaws and. ') print() time.sleep(2) friendlyCave = random.randint(1, 2) if chosenCave == str(friendlyCave): print('Gives you his treasure') else: print('Gobbles you down in one bite!') playAgain = 'yes' while playAgain == 'yes' or playAgain == 'y': displayIntro() caveNumber = chooseCave() checkCave(caveNumber) print('do you want to play again? (yes or no)') playAgain = input() 

  I don’t understand the def checkCave(chosenCave): parts, why does the argument say chosenCave ? Can someone explain please?

  chosenCave becomes a local variable that you passed to the function. You can then access the value inside that function to process it, provide whatever side-effects you’re looking to provide (like printing to the screen, as you’re doing), and then return a value, (which if you don’t do explicitly, Python returns None , its null value, by default.)

  Algebraic Analogy

  In algebra we define functions like this:

  In Python we define functions like this:

  and in keeping with the above simple example:

  When we want the results of that function applied to a particular x, (e.g., 1), we call it, and it returns the result after processing that particular x.:

  particular_x = 1 f(particular_x) 

  And if it returns a result we want for later usage, we can assign the results of calling that function to a variable:

  The name chosenCave appears to have been chosen to describe what it represents, namely, the cave the player chose. Were you expecting it to be named something else? The name isn’t required to match or not match any names located elsewhere in the program.

  How do Arguments and Parameters Work in Python?, In the function. def checkCave(chosenCave): chosenCave becomes a local variable that you passed to the function. You can then access the value …

  Difference bewteen *args and **args in python? [duplicate]

  I am trying to understand the difference between *args and **args in function definition in python. In the below example, *args works to pack into a tuple and calculate the sum.

  >>> def add(*l): . sum = 0 . for i in l: . sum+=i . return sum . >>> add(1,2,3) 6 >>> l = [1,2,3] >>>add(*l) 6 

  >>> def f(**args): . print(args) . >>> f() <> >>> f(de="Germnan",en="English",fr="French") >>> 

  I see that it takes parameters and turns into a dictionary. But I do not understand the utility or other things that could be helpful when using ** args. In fact, I dont know what *args and **args are called(vararg and ?)

  When you use two asterisks you usually call them **kwargs for keyword arguments. They are extremely helpful for passing parameters from function to function in a large program.

  A nice thing about keyword arguments is that it is really easy to modify your code. Let’s say that in the below example you also decided that parameter cube is also relevant. The only thing you would need to do is add one if statement in my_func_2 , and you would not need to add a parameter to every function that is calling my_func_2 , (as long as that functions has **kwargs ).

  Here is a simple rather silly example, but I hope it helps:

  def my_func_1(x, **kwargs): if kwargs.get('plus_3'): return my_func_2(x, **kwargs) + 3 return my_func_2(x, **kwargs) def my_func_2(x, **kwargs): #Imagine that the function did more work if kwargs.get('square'): return x ** 2 # If you decided to add cube as a parameter # you only need to change the code here: if kwargs.get('cube'): return x ** 3 return x 

  >>> my_func_1(5) 5 >>> my_func_1(5, square=True) 25 >>> my_func_1(5, plus_3=True, square=True) 28 >>> my_func_1(5, cube=True) 125 

  Positional Arguments vs Keyword Arguments in Python, Hence, we can say that an argument is a value that is passed to a function, and a parameter is the variable declared in the function to which the argument is …

  What is the difference between data and params in requests?

  I am using python requests module, I send my params like this before:

  requests.post(url=url, params=params) 

  but today, I find that I send my data like this, it fails, I change to this:

  requests.post(url=url, data=params) 

  then it is ok, what is the difference between data and params ?

  I observed that the request got a header X-Requested-With:XMLHttpRequest , is it because of this?

  According to the requests documentation:

  • A requests.post(url, data=data) will make an HTTP POST request, and
  • A requests.get(url, params=params) will make an HTTP GET request

  To understand the difference between the two, see this answer.

  Here’s how params can be used in a GET:

  payload = r = requests.get('http://httpbin.org/get', params=payload) print(r.text) 

  < "args": < "key1": "value1", "key2": "value2" >, [. ] "url": "http://httpbin.org/get?key1=value1&key2=value2" > 

  Notice that the payload ended up in the query string of the URL. Since they ended up there, they are viewable by anyone who has access to the URL, which is why you shouldn’t use query strings for sensitive data like passwords.

  Here’s how data can be used in a POST:

  payload = 'foobar' r = requests.post('http://httpbin.org/post', data=payload) print(r.text) 

  < "args": <>, "data": "foobar", [. ] "url": "http://httpbin.org/post" > 

  Notice how the POST data does not show up in the query strings, as they are transmitted through the body of the request instead.

  Critique of this answer has pointed out that there are more options. I never denied such a thing in my original answer, but let’s take a closer look.

  The documentation examples always show:

  But that doesn’t mean they are mutually exclusive.

  In theory you could mix the two together in a POST:

  data = 'foobar' params = r = requests.post('http://httpbin.org/post', params=params, data=data) print(r.text) 

  < "args": < "key1": "value1", "key2": "value2" >, "data": "foobar", [. ] "url": "http://httpbin.org/post?key1=value1&key2=value2" > 

  But you cannot mix data into a GET:

  data = 'foobar' params = r = requests.get('http://httpbin.org/get', params=params, data=data) print(r.text) 

  < "args": < "key1": "value1", "key2": "value2" >, [. ] "url": "http://httpbin.org/get?key1=value1&key2=value2" > 

  Notice how the data field is gone.

  First of all, there are two different methods :

  • requests.post() makes a POST request (placing all the parameters in the body)
  • requests.get() makes a GET request (placing all the parameters in the URL)

  Then, according to the docs, you can choose between two parameters to send all the key/value data:

  • params= , without string modifications.
  • data= , applying a form-encoding string modification to the parameters.

  So, you have 4 choices to send your request:

  • requests.post(url, params=)
  • requests.post(url, data=)
  • requests.get(url, params=)
  • requests.get(url, data=)

  I don’t think the currently accepted answer is correct. He is actually talking about requests.post() but using requests.get() in his own example.

  Params are sent in (appended to) the URI ( http://www.answer.com/here?param1=1&param2=2 ) while data is sent in the request body. Usually sensitive data or that sent in large volumes is posted in the body because it’s easier to secure and doesn’t lead to huge URIs.

  Python — Parameter vs Arguments ? finally,what are, Some say,parameters are variables which we give them to functions while we are defining them and arguments are values that are passed in …

  Источник

  Python Function Arguments

  Information can be passed into functions as arguments.

  Arguments are specified after the function name, inside the parentheses. You can add as many arguments as you want, just separate them with a comma.

  The following example has a function with one argument (fname). When the function is called, we pass along a first name, which is used inside the function to print the full name:

  Example

  def my_function(fname):
  print(fname + » Refsnes»)

  my_function(«Emil»)
  my_function(«Tobias»)
  my_function(«Linus»)

  Arguments are often shortened to args in Python documentations.

  Parameters or Arguments?

  The terms parameter and argument can be used for the same thing: information that are passed into a function.

  From a function’s perspective:

  A parameter is the variable listed inside the parentheses in the function definition.

  An argument is the value that are sent to the function when it is called.

  Number of Arguments

  By default, a function must be called with the correct number of arguments. Meaning that if your function expects 2 arguments, you have to call the function with 2 arguments, not more, and not less.

  Example

  This function expects 2 arguments, and gets 2 arguments:

  def my_function(fname, lname):
  print(fname + » » + lname)

  Example

  This function expects 2 arguments, but gets only 1:

  def my_function(fname, lname):
  print(fname + » » + lname)

  Источник