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Wolverine .py
2,513 Pointshiya i am stuck how do i make a function called add_list with only numbers in it and should return the total
Make a function named add_list that takes a list. The function should then add all of the items in the list together and return the total. Assume the list contains only numbers. You'll probably want to use a for loop. You will not need to use input().
add_list = list([1, 2, 3])
def add_list([1, 2, 3]):
return 1+2+3
# summarize([1, 2, 3]) should return "The sum of [1, 2, 3] is 6."
# Note: both functions will only take *one* argument each.
3 Answers
Nathan Smutz
9,492 PointsIt looks like you're having trouble with functions. Here's how they look:
def i_am_a_function( i_am_an_argument ):
... (we do something with the i_am_an_argument here)...
return i_am_the_thing_the_function_returns
When you use the function it looks like this:
i_will_equal_the_thing_the_function_returns = i_am_a_function( a_variable_or_something )
or if you just want to print things out:
print(i_am_a_function( a_variable_or_something ))
Here's how your function will look in usage:
my_list = [1, 2, 3, 4]
sum_of_my_list = add_list(my_list)
print(sum_of_my_list)
>>>10
or:
add_list([1,2,3,4])
>>> 10
So we've been told that our function needs to take a list and add up the numbers in the list and return the total. So we know this much:
def i_am_a_function( i_am_a_list ):
...(add up the numbers in the list)...
return the_total_of_the_numbers_in_the_list
Let's rename things a little to match what you're doing:
def add_list( list_of_numbers ):
...(add all the numbers together so that the sum is named "total")...
return total
Here is is fleshed out:
def add_list ( list_of_numbers ):
total = 0; # We will add all the numbers to this variable
for i in list_of_numbers: # For each number in the list
total = total + i # add that number to the sum of all the previous numbers
return total # Return the total
Used like this:
my_list = [1, 2, 3, 4]
sum_of_my_list = add_list(my_list)
print(sum_of_my_list)
>>>10
or:
add_list([1,2,3,4])
>>> 10
Wolverine .py
2,513 PointsThank you very helpful. i got the concept, i have done everything you have taught me.
Nathan Smutz
9,492 PointsNice :-) Did the rest of the exercise work out well?
Wolverine .py
2,513 Pointsthank you Nathan, you pretty much helped me with everything. and it worked. you the man!!!!!!!!. i will ask you any questions if i am stuck hey.