5.1. Average Weight of Deliveries

Suppose a shipping company needs your help to analyze the recorded weights of their deliveries and calculate the average weights within a range.

Write a function named average_weight which gets a string as a file name where the weights are recorded as integers separated with a blank character in multiple lines. This function must return a float which is the average for the deliveries weighted in the range of [45, 125] kilograms. If there is no recorded delivery in the given range, the function must return 0.

Hint: You can use built-in map() and filter() functions.

Sample I/O:

Sample function call:
    average_weight("input.txt")

Content of the file "input.txt":
    61 49 92 159 212 257 107 320
    237 282 354 240 120 330 243
    95 113 300 114 271
    191 303 396 117 175 350

Return value:
    96.444444

Show the Answer

def average_weight(input_path):
    min_weight = 45
    max_weight = 125
    weights_in_range = []
    input_file = open(input_path, 'r')    # open input file in read mode
    for line in input_file.readlines():
        all_weights = list(map(int,list(line.split())))   # getting integer values in a line.
        filtered = list(filter(lambda x: int(x) >= min_weight and int(x) <= max_weight, all_weights))   # filtering the weights
        weights_in_range += filtered

    input_file.close()    # do not forget to close

    count = 0
    total = 0
    for w in weights_in_range:
        total += w
        count += 1
    if count:
        return (total / count)
    else:
        return 0