List manipulation in functions


#1



What's wrong with my code?


Oops, try again. list_extender([1, 2, 3, 4]) returned [1, 2, 3, 4, 9, 9] instead of [1, 2, 3, 4, 9]


n = [1,2,3,4]
# Add your function here
def list_extender(lst):
    n.append(9)
    return n
print list_extender(n)


#2

Hi @arcjumper70888 ,

The instructions include ...

Inside the function, append the number 9 to lst.

Then return the modified list.

... but you have ...

    n.append(9)
    return n

You modified and returned the global list, n, instead of lst.


#3

@arcjumper70888
You should understand that your list_extender() function
is using a parameter lst
which you then use as a variable lst within the function-body.....

Please read the Function talk
and concentrate on
parameter
argument
print vs return statement

the FUNCTION talk

def myFunc( param1, param2):
    # Begin of =myFunc= FUNCTION-BODY
    # this =myFunc= function- has 2 PARAMETERS param1 and param2
    # param1 and param2 PARAMETERS are used 
    # as -local- VARIABLES throughout the =myFunc= FUNCTION-BODY
    print( param1 + " and " + param2 )
    #End of =myFunc= FUNCTION-BODY

If you want to call/execute the myFunc function
you will have to add a pair of parentheses to myFunc
like
myFunc()
As the myFunc function was defined
as having 2 parameters
you have to provide 2 arguments
in our case 2 string VALUES "Alena" and "Lauren"
like
myFunc("Alena","Lauren")

some quotes from the outer-world:

**argument is the value/variable/reference being passed in,
parameter is the receiving variable used within the function/block**

OR

**"parameters" are called "formal parameters",
while "arguments" are called "actual parameters".**

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
++++ function with 1 parameter using return-statement

def myFunction( param1 ):
    # //Begin of =myFunction= FUNCTION-BODY
    # //=myFunction= function has 1 PARAMETER param1
    # //this param1 PARAMETER is used as a -local- VARIABLE
    # //throughout the =myFunction= FUNCTION-BODY
    return param1;
    # //End of FUNCTION-BODY

You have defined a myFunction function
which takes 1 parameter param1
this param1 parameter is used
as a variable throughout the =myFunction= FUNCTION-BODY.

If you want to call/execute this myFunction function
and this myFunction function was defined
as having 1 parameter param1
you will have to provide 1 argument
in our case a "number VALUE" 4
myFunction( 4 )

some quotes from the outer-world:

**argument is the value/variable/reference being passed in,
parameter is the receiving variable used within the function/block**

OR

**"parameters" are called "formal parameters",
while "arguments" are called "actual parameters".**


#4

Hi appylpye. Thank you very much,


#5

Thank very much. Your advise give me a big help^^


#7

Thanks a lot.. I got it.


#8

This is my code:

n = [1, 2, 3, 4]
def list_extender(lst):
n.append(9)
return n
print list_extender(n)

I get this:

Oops, try again. list_extender([1, 2, 3, 4]) returned [1, 2, 3, 4, 9, 9] instead of [1, 2, 3, 4, 9]
Can someone please suggest what I need to be doing to to get it right?


#9

Hi 13kiran
This is my code:

n = [1,2,3,4]
def list_extender(lst):
lst.append(9)
return lst
print list_extender(n)


#10

Thank you Arcjumper. It worked.


#11

n = [3, 5, 7]
def print_list(x):
    for i in range(0, len(x)):
        print x[i]
print_list(n)

`


#12

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