# Need help in lesson 9/9

#1
``````lloyd = {
"name": "Lloyd",
"homework": [90.0, 97.0, 75.0, 92.0],
"quizzes": [88.0, 40.0, 94.0],
"tests": [75.0, 90.0]
}
alice = {
"name": "Alice",
"homework": [100.0, 92.0, 98.0, 100.0],
"quizzes": [82.0, 83.0, 91.0],
"tests": [89.0, 97.0]
}
tyler = {
"name": "Tyler",
"homework": [0.0, 87.0, 75.0, 22.0],
"quizzes": [0.0, 75.0, 78.0],
"tests": [100.0, 100.0]
}

def average(numbers):
total = sum(numbers)
return float(total)/len(numbers)
def get_average(lloyd):
homework = average (lloyd["homework"])
quizzes = average(lloyd["quizzes"])
tests = average(lloyd["tests"])
return 0.1 * homework + 0.3 * quizzes + 0.6 * tests
if score >= 90:
return "A"
elif score >= 80:
return "B"
elif score >= 70 :
return "C"
elif score >= 60:
return "D"
else :
return "F"

def get_class_average(class_list):
results = []
for student in class_list:
student_average = get_average(student)
results.append(student_average)
return average(results)

students = ("lloyd","alice","tylor")
print get_class_average(students)
``````

the error message on console is : B
Traceback (most recent call last):
File “python”, line 50, in
File “python”, line 45, in get_class_average
File “python”, line 25, in get_average
TypeError: string indices must be integers, not str

#2

here:

``````students = ("lloyd","alice","tylor")
``````

why are you students strings, i mean here:

``````print get_letter_grade(get_average(lloyd))
``````

you use the dictionary stored in a variable `lloyd`, so you realize that the students should refer to the dictionary, i am unsure why you use strings in the list

also, `get_average(lloyd)`, the function has a parameter of `lloyd`, why? it could be any `student`

#3

Thanks i removed the quotation

#4

ok you are saying it could be students instead of lloyd right?

#5

but do you also understand what implications this has on your program?

well, `student` would be even a better name, given get_average takes a single student as argument. but then these lines:

``````  homework = average (lloyd["homework"])
quizzes = average(lloyd["quizzes"])
tests = average(lloyd["tests"])
``````

also need updating

#6

Yes I do understand what implications it has for my program
letters inside of quotation are strings and I was calling string lloyd instead of dictionary lloyd

#7

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