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Test grade average python / n.append(float(score)) AttributeError: 'int' object has no attribute 'append'

Receiving this error :
n.append(float(score))
AttributeError: 'int' object has no attribute 'append'.
After running code below:
def averageTestScore(n):
total = 0
for x in range(n):
total += x #sum of numOf tests taken
avg = total / len(str(n))
for counter in range(0, n):
score = float(input("What was your score on test # "))
# n.append(float(score))
# score += counter
return avg
numberOfTests = int(input("How many tests did you take? "))
average = averageTestScore(numberOfTests)
print("The average of those test scores is:", average)

In your code given above , you were trying to append an integer to another integer (Note n is the number of tests you had used as a function parameter, that's why you got an Error).
I think what you want is to get average of tests.
So, I think this may help you
def averageTestScore(n):
tt=0
for i in range(n):
sc=float(input("What was your score on test : "))
tt+=sc
return tt/n
numberOfTests = int(input('How many tests did you take ? '))
average = averageTestScore(numberOfTests)
print("The average of those test scores is :", average)

Change your code to -
def averageTestScore(n):
score = 0
for num in range(1,n+1):
score += float(input(f"What was your score on test {num} "))
avg = score/n
return avg
numberOfTests = int(input("How many tests did you take? "))
average = averageTestScore(numberOfTests)
print("The average of those test scores is:", average)
Then it should work without error.
You got error, because you cannot append to a integer, only to a list you can append. So, try this different approach. I used f-strings so that the test number is also shown.

Using a function calculate and display the average of all numbers from 1 to the number entered by the user in python

I am gitting stuck here, please help. The code has to promt the user to enter a number, pass the number to a python function and let the function calculate the average of all the numbers from 1 to the number entered by the user.
def SumAverage(n):
sum=0
for idx in range(1,n+1):
average =sum/idx
return average
num =int(input("Enter a number"))
result=SumAverage(num)
print("The average of all numbers from 1 to {} is {}".format(num,result))

The sum of the series 1 + 2 + 3 + ... + n where n is the user inputted number is:
n(n+1)/2 (see wikipedia.org/wiki/1+2+3+4+...)
We have that the average of a set S with n elements is the sum of the elements divided by n. This gives (n(n+1)/2)/n, which simplifies to (n+1)/2.
So the implementation of the average for your application is:
def sum_average(n):
return (n + 1) / 2
This has the added benefit of being O(1).

Your version is not working because the average is always set to the last calculation from the for loop. You should be adding the idx for each iteration and then doing the division after the loop has completed. However, all of that is a waste of time because there is already a function that can do this for you.
Use mean from the statistics module.
from statistics import mean
num = int(input("Enter a number"))
result = mean(list(range(1, num+1)))
print(f'The average of all numbers from 1 to {num} is {result}')
If you are determined to do the logic yourself it would be done as below, if we stick with your intended method. #zr0gravity7 has posted a better method.
def SumAverage(n):
sum=0
for i in range(1,n+1):
sum += i
return round(sum / n, 2)
num = int(input("Enter a number"))
result = SumAverage(num)
print(f'The average of all numbers from 1 to {num} is {result}')
I'm not recommending this, but it might be fun to note that if we abuse a walrus (:=), you can do everything except the final print in one line.
from statistics import mean
result = mean(list(range(1, (num := int(input("Enter a number: ")))+1)))
print(f'The average of all numbers from 1 to {num} is {result}')

I went ahead and wrote a longer version than it needs to be, and used some list comprehension that would slow it down only to give some more visibility in what is going on in the logic.
def SumAverage(n):
sum=0
l = [] # initialize an empty list to fill
n = abs(n) # incase someone enters a negative
# lets fill that list
while n >= 1:
l.append(n)
print('added {} to the list'.format(n), 'list is now: ', l)
n = n - 1 # don't forget to subtract 1 or the loop will never end!
# because its enumerate, I like to use both idx and n to indicate that there is an index and a value 'n' at that index
for idx, n in enumerate(l):
sum = sum + n
# printing it so you can see what is going on here
print('length of list: ', len(l))
print('sum: ', sum)
return sum/len(l)
num =int(input("Enter a number: "))
result=SumAverage(num)
print("The average of all numbers from 1 to {} is {}".format(num,result))

Try this:
def SumAverage(n):
sum=0
for i in range(1,n+1):
sum += i
average = sum/n
return average

[its the better plz see this.
(short description):- user enter the list through functions then that list is converted into int. And the average is calculated all is done through functions thanx
]1

Debugging a simple Python price code

I have this code in Python
def receipt(array):
sum = 0.0
for i in range(len(array)):
sum = sum + array[i]
return sum
array = []
while True:
print("Calculating Price")
n = input("Enter a price: ")
if n == "":
print("Goodbye")
break
array.append(n)
totalCost = receipt(n)
print("The total cost is " + str(totalCost))
And I'm wondering why this code won't work. There seems to be some error in the fourth line
sum = sum + array[i]
But I can't figure out which part of it is wrong. I believe I used the array[i] component correctly. Perhaps it's a string issue?
Question:
Which part of the code doesn't work?
What is my error?
I'm relatively new to computer science in general. Thanks for the help. Anything is appreciated!

I ran your code and got this error:
$ python test.py
Calculating Price
Enter a price: 24
Traceback (most recent call last):
File "test.py", line 14, in <module>
totalCost = receipt(n)
File "test.py", line 4, in receipt
sum = sum + array[i]
TypeError: unsupported operand type(s) for +: 'float' and 'str'
This means that in your sum = sum + array[i] line, the types don't match up. You need to wrap array[i] in a float() function to match array[i] to the type of sum, which is a float since you initialized it to 0.0. The docs say the input() function returns a string, and since you're appending n to array, you are trying to sum a string with a float. The line should look like this:
sum = sum + float(array[i])
Try running it again and the code works. Here is the documentation for input()
Edit: now to fix the issues were were having with the sum.
Here is a version of your code I have revised with corrections to do the addition the way you want.
1 def receipt(sumvar, n):
2 sumvar = sumvar + float(n)
3 return sumvar
4
5 array = []
6 sumvar = 0.0
7
8 while True:
9 print("Calculating Price")
10 n = input("Enter a price: ")
11 if n == "":
12 print("Goodbye")
13 break
14 totalCost = receipt(sumvar, n)
15 sumvar = totalCost
16 print("The total cost is " + str(totalCost))
As mentioned by others, sum isn't a great variable name so I've renamed it sumvar. Notice the sumvar declaration that is outside the function. When you initialize sumvar inside receipt() like you did, you will always be adding n to 0.0. I doubt this is what you want. Instead, you want to keep a running total of the item count, which needs to be passed into the function. I've also eliminated the loop from your function. This loop was actually iterating over the characters in array, not the elements as you expected it to.

First of there are several things wrong. I will explain each and everything.
Here is your complete working code:
def receipt(array):
total = 0.0
for i in array:
total = total + i
return total
array = []
while True:
print("Calculating Price")
n = input("Enter a price: ")
if n=="":
print("Goodbye")
break
array.append(float(n))
totalCost = receipt(array)
print("The total cost is " + str(totalCost))
Your Mistakes:
1)array.append(n) - First one. Pretty common for beginner.
input() in python gets user input as string. So your n is a String.
See there are data types in all languages. And Python is a Strongly typed language while perl is not. How to say if a language is strongly typed or weakly typed ? Simple. Try this in your interpreter.
>>> a=5
>>> b='9'
>>> a+b
Traceback (most recent call last):
File "<pyshell#5>", line 1, in <module>
a+b
TypeError: unsupported operand type(s) for +: 'int' and 'str'
See the error now try this,
>>> a=5
>>> b='9'
>>> a+int(b)
14
Works perfectly fine right. Python doesn't allow just a+b while some languages do example perl. Read more about it. So you can't add them you have to typecast. So change that into
array.append(int(n))
or
array.append(float(n))
If you are going to work with float values.
2) totalCost = receipt(n) See you are passing n to the function. But your function definition has def receipt(array):. What actually happens here is
receipt(n) ----> (calls) ---->def receipt(array):
Where n ------> array So your array is nothing but n. What you should do intead is
totalCost = receipt(array)
3) sum = 0.0 NEVER I said never use built-in or keyword names (ex ample : sum,min,max,int,str etc) as variable names. Read more about naming in PEP 8
So maybe rename sum to sum_ (it's the convention to be followed) However why can't you just rename sum to total much simpler right?
4) And finally
for i in range(len(array)):
sum = sum + array[i]
Why range(len(array)) when you can simply do for i in array:
Can't understand this take a look at this example:
>>> a = [1,2,3]
>>> for i in a:
print(i)
1
2
3
See for item in something would just take each and every item from a group of something ( iterable (list,tuple,set etc..))
So just change those lines to
for i in array:
total = total + i
And voila you got what you wanted,
Output:
Calculating Price
Enter a price: 10
The total cost is 10.0
Calculating Price
Enter a price: 20
The total cost is 30.0
Calculating Price
Enter a price: 15
The total cost is 45.0
Calculating Price
Enter a price:
Goodbye
UPDATE:
As mentioned in comments you need to learn more about indentation. Check out the link in the comments.

You have some problems, I will comment one by one:
First, you had some indentation problems, be careful with that.
The rest are comments in the code
update
def receipt(array):
sum = 0.0
for i in range(len(array)):
sum = sum + array[i]
return sum
array = []
while True:
print("Calculating Price")
n = input("Enter a price: ") #If you convert the str into float here it will cause an error in the if
if n == "": #here, when you hit enter, it sends the "" (empty string)
print("Goodbye")
break
array.append(float(n)) #So an option is transform the string here
totalCost = receipt(array) #and here, you gave to receipt() function the wrong param, you gave "n" and it was waiting for an array
print("The total cost is " + str(totalCost))

You shouldn't use sum as a variable, since it's a built-in in Python, besides, convert your array[i] to a float type when adding it to another float, also notice you never use your initialized array, you are missing that when calculating totalCost:
def receipt(array):
summ = 0.0
for i in range(len(array)):
summ = summ + float(array[i])
return summ
array = []
while True:
print("Calculating Price")
n = input("Enter a price: ")
if n == "":
print("Goodbye")
break
array.append(n)
totalCost = receipt(array)
print("The total cost is " + str(totalCost))

I have corrected what is causing your issue, you are in fact passing in 'n' into receipt instead of 'array'.
def receipt(array):
sum = 0.0
for i in range(len(array)):
sum = sum + array[i]
return sum
array = []
while True:
print('Calculating Price')
n = input("Enter a price: ")
if n == "":
print("Goodbye")
break
array.append(n)
totalCost = receipt(array) #receipt takes a list as a parameter (what you call array)
print("The total cost is " + str(totalCost))
Additional issues are:
indentation (I suspect that was just copy paste)
input will also give you errors the way you are using it, take a look at this to solve that issue
Consider also making your loop based on the value of n as while true is generally unsafe
or at least changing your if statement to be 'not n' as point out here is more pythonic. Also in the future make sure to note the version of python you are using.

Dont use sum as a variable name, it is a Python built-in.
Fixed:
def receipt(array):
total = 0.00 # avoiding 'sum'
for price in array:
total += float(price) # equivalent to 'total = total + float(price)'
return total
array = []
print ("Calculating Price...") # outside 'while' to not reprint each time!
while True:
price = input("Enter a price: ")
if not price: # equivalent to 'if price is False, or 0 in CompSci speak
print ("Goodbye!")
break
array.append(price)
total = receipt(array)
print("The current total cost is", total) # no need to convert to str()
Some words of advice:
When writing a function, its better to be explicit rather than
implicit. So use variables that make sense!
We can use the same variable names because Python uses the LEBG
rule
for variable scope.
When calculating a price (which we know usually ends in 2 decimals)
its better to use integers rather than floats as you will run into
the [problem](
Limiting floats to two decimal points)
with floating point numbers.

Python- Function that returns a value

Im really struggling with this question, can anyone help me write a code for this program? or at least say where am I going wrong? Ive tried a lot but can't seem to get the desired output.
This is the program description: Python 3 program that contains a function that receives three quiz scores and returns the average of these three scores to the main part of the Python program, where the average score is printed.
The code I've been trying:
def quizscores():
quiz1 = int(input("Enter quiz 1 score: "))
quiz2 = int(input("Enter quiz 2 score: "))
quiz3 = int(input("Enter quiz 3 score: "))
average = (quiz1 + quiz2 + quiz3) / 3
print (average)
return "average"
quizscores(quiz1,quiz2,quiz3)

One, you are returning a string, not the variable. Use return average instead of return "average". You also don't need the print() statement in the function... actually print() the function.
If you call a function the way you are doing it, you need to accept parameters and ask for input outside the function to prevent confusion. Use a loop as needed to repeatedly use the function without having to rerun it every time. So the final code would be:
def quiz_average(quiz1, quiz2, quiz3):
average = (quiz1 + quiz2 + quiz3) / 3
return average
quiz1 = int(input("Enter Quiz 1 score: "))
quiz2 = int(input("Enter Quiz 2 score: "))
quiz3 = int(input("Enter Quiz 3 score: "))
print(quiz_average(quiz1, quiz2, quiz3)) #Yes, variables can match the parameters

You are returning a string instead of the value. Try return average instead of return "average".

There are a few problems with your code:
your function has to accept parameters
you have to return the actual variable, not the name of the variable
you should ask those parameters and print the result outside of the function
Try something like this:
def quizscores(score1, score2, score3): # added parameters
average = (score1 + score2 + score3) / 3
return average # removed "quotes"
quiz1 = int(input("Enter quiz 1 score: ")) # moved to outside of function
quiz2 = int(input("Enter quiz 2 score: "))
quiz3 = int(input("Enter quiz 3 score: "))
print(quizscores(quiz1,quiz2,quiz3)) # print the result

An alternative answer to the already posted solutions could be to have the user input all of their test scores (separated by a comma) and then gets added up and divided by three using the sum method and division sign to get the average.
def main():
quizScores()
'''Method creates a scores array with all three scores separated
by a comma and them uses the sum method to add all them up to get
the total and then divides by 3 to get the average.
The statement is printed (to see the average) and also returned
to prevent a NoneType from occurring'''
def quizScores():
scores = map(int, input("Enter your three quiz scores: ").split(","))
answer = sum(scores) / 3
print (answer)
return answer
if __name__ == "__main__":
main()

Python 2 - "For counting loop"

I am working on a project for school in python 2 and I am having a lot of trouble with one of the problems:
Write a program that computes the following sum:
sum = 1.0/1 + 1.0/2 + 1.0/3 + 1.0/4 + 1.0/5 + .... + 1.0/N
N is an integer limit that the user enters.
For example:
Enter N: 4
Sum is: 2.08333333333
The code I currently have written is:
NumOfN = int(input("What is N? : "))
total = 0
for i in range (NumOfN):
NextNum = 1.0/(NumOfN)
total = NextNum
NumOfN = NumOfN-1
print "the sum is", total
However whenever I run this I get an output of "1.0" any help would be greatly appreciated.
-Thank you.

You were not incrementing total with itself and NextNum. I changed total = NextNum to total += NextNum:
NumOfN = int(input("What is N? : "))
total = 0
for i in range(NumOfN):
NextNum = 1.0/(NumOfN)
total += NextNum
NumOfN = NumOfN-1
print "the sum is ", total
or more simply:
NumOfN = int(input("What is N? : "))
runningTab = []
for i in range(NumOfN, -1, -1):
if i != 0:
runningTab.append(1.0/(i))
print "the sum is ", sum(runningTab)
It is better to use lists and sum at the end than to keep a running tally of numbers.

Second line of the for loop:
total = NextNum
The variable total should have NextNum added to it, not just reassigned. This is because total must be added over and over by adding NextNum to itself. Let's change that to:
total = total + NextNum
This would mean: total needs to add NextNum to itself, so we will add them together so that the new total is now equal to the old total + NextNum.
A side note:
You may have noticed that #heinst used += in his line of code, total += NextNum. This is the same as total = total + NextNum , but it is like an abbreviation. You can do this with += , -= , *=,and /=. All of them are ways to abbreviate the line of code that would reassign a variable after doing some arithmetic on it.
With that being said, the following line of code:
NumOfN = NumOfN-1
Can become:
NumOfN -= 1
This is an abbreviation.