Question

Define a function below called average_num_in_file. The function takes one argument: the name of a file full of numbers. Complete the function so that it opens the file and returns the average of the numbers in the file. Here is an example input file from the static test case if you want to test from the interpreter: canned_file.txt

Answer 1

Answer:

1. def average_num_in_file(fileName):
2.    with open(fileName) as file:
3.        rows = file.readlines()
5.        sum = 0
6.        count = 0
7.        for x in rows:
8.            sum += float(x)  
9.            count += 1
11.        average = sum / count  
12.    return average  
14. print(average_num_in_file("cans.txt"))

Explanation:

The solution code is written in Python 3.

Firstly create a function that take one parameter, fileName (Line 1).

Open the file stream and use readlines method to read the data from the file (Line 2-3). Create variable sum and count to tract the total of the number from text files and number of data from the file (Line 5-6). Use a for loop to loop over each row of the read data and add the current value of each row to sum and increment the count by one (Line 7-9).

After the loop, calculate the average (Line 11) and return the result (Line 12).

At last, we can test the function by passing the cans.txt as argument (Line 14).