Part of the Whole


#1

where is my wrong??

def get_class_average(students):
students = [lloyd, alice, tyler]
results = []
for student in students:
get_average(student)
results.append(get_average(student))
return average(results)

Oops, try again. get_class_average([alice]) returned 83.8666666667 instead of 91.15 as expected


#2

@shiransiboni,

First of all you have to understand the working of a function
as it can take a parameter
and when you call the function
you are providing a so-called argument

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".**

============================================

As you are using the return-statement in your myFunction function
you will only get a return-value no-display.
You can however capture this return-value in a variable
and then use the print-method to do a display.

theResult = myFunction( 4 )
print theResult

OR directly

print myFunction( 4 )

#3

@shiransiboni,

Now if you define the get_class_average() function
like

def get_class_average(students):

you have defined the get_class_average() function as taking 1 parameter students

This students parameter
will be used as a =local= variable in the FUNCTION-BODY ( in the code-block of the function)
thus

def get_class_average(students):
    # Begin of FUNCTION-BOY
    # PARAMETER student is a =local= VARIABLE
    #
    tot_avg = 0
    list_result = []
    for student in students:
        # we expect the =students= VARIABLE to be a =list=
        # and we expect each =list-Element= to be a =dictionary=
        new_avg = get_average(student)
        # tot_avg = tot_avg + new_avg
        # or in shorthand
        tot_avg += new_avg
        list_result.append(new_avg)
    # end of FOR-loop
    # calculate the real average
    list_real_avg = sum(list_result) / len(students)
    tot_real_avg = tot_avg / len(students)
    print("{0} {1}".format(tot_real_avg,tot_real_avg))
    return tot_real_avg

As you have defined 3 variables lloyd, alice and tyler
to each of which you assigned a dictionary Value
and the get_class_average() function expects you to use a =list= of =dictionaties=
you could call the get_class_average() function
like

print get_class_average([lloyd,alice])

#4

This answer seems to be more complicated and redundant than called for so far in the lesson.