Question

Write a function called st_dev. St_dev should have one #parameter, a filename. The file will contain one integer on #each line. The function should return the population standard #deviation of those numbers.

Answer 1

Answer:

1. import statistics
3. def st_dev(file_name):
4.    with open(file_name) as file:
5.        data = file.readlines()
6.        numList = []
7.        for x in data:
8.            numList.append(int(x))
9.        
10.        return statistics.pstdev(numList)
12. print(st_dev("text1.txt"))

Explanation:

The solution code is written using Python.

To ease the calculation task, we can import Python statistics module to use the pstdev method to calculate the population standard deviation of a list of numbers (Line 1).

Next, create a st_dev function that take single argument file_name (Line 3). In the function, it will open the input file and read the data line by line (Line 4-5). Create a for loop to traverse through each line of the data which is an integer and append it to numList (Line 7-8). We can pass the numList to pstdev method (Line 10) and return the resulting standard deviation value as output.

We test the function by passing a file which hold a list of integer values in each line (Line 12).

8

9

12

11

21

15

16

10

7

13

And the output we shall get is 4.019950248448356