Cfrgtkky

I have to create a program that reads a text file of lengths of boards. I have to find and print the average of these lengths. Then I have to print a table of lengths and their differences from the mean. Then I need to count how many differences are > 0.10.

So far I have been able to find the average of the boards and I have been able to count the amount of differences more than > 0.10. But I cannot figure out how to append the lengths and differences into a list to be able to print each length with the difference next to it.

Code:

dif = 0

total = 0

count = 0

avg = 0

difcount = 0

boards = 

with open("boards.txt", "r") as fo:

    for line in fo:

        length = float(line)

        total += length

        count += 1

        avg = total/count

        dif = length - float(avg)

        if dif > float(0.10):

            difcount += 1

    print("Average:", round(avg,2))

    for line in fo:

        print(length, dif)

    print("Number of boards > 0.10 from average:", difcount)

Output:

average: 7.97

Number of boards > 0.10 from average:3

I can't figure out how to print my table of lengths and differences

Length    Difference

#         #

#         #

# and so on

Your computations aren't in the correct order. You can't do any differences until you know the mean of the inputs. At the moment, there's no way for the first board to get flagged, because your avg at that point is nothing more than the first board's length.

You need to handle this in steps:

1. Read all the data into a list


2. Compute the average


3. Go back through the list, checking each item against the average.

In this third step, you should have an easy time producing your output.

Can you take it from there?

I don't think your length variable is instantiated when you're trying to print it.
You could create a tuple array to hold your lengths and difs:


for line in fo:

boards.append((length, dif))
for item in boards:
print(item)


that way you'd have them after reading the text file.

Prune's answer is true, I don't think you are calculating the averages correctly.

I think that you should first loop though all the boards and store their length in a list

board_lengths = 

with open("boards.txt", "r") as fo:

    for line in fo:

        board_lengths.append(float(line))

After you have done this you could sum up the list to create you mean

import numpy as np

mean_board_length = np.mean(board_lengths)

You could find then find the differences

differences = [l - mean_board_length for l in board_lengths]

and the amount of times when the difference is greater than 0.1

times = np.sum([d>0.1 for d in differences])