Trying to have python function return frequency table

Asked Mar 19 '21 at 18:27

Active Mar 19 '21 at 18:27

Viewed 37 times

opened_file = open(r'C:\Users\lalus\Desktop\Datasets\cars.csv')
from csv import reader
read_file = reader(opened_file)
cars_data = list(read_file)

def howMany(index):
    a_list = {}

    for row in cars_data[1:]:
        if row[index] in a_list:
           a_list[index] += 1
        else:
            a_list[index] = 1

return a_list

make_count = howMany(2)

print(make_count)

My csv file has a row for the make of a series of cars at index 2. I want the output to return a list of the make a a car along with the number of times the make appears in the column.

so far this code only returns {2:1}.

What am I missing?

asked Mar 19 '21 at 18:27

Raul Quintanilla Jr.

`return a_list` needs to be indented inside the function. – Barmar Mar 19 '21 at 18:29
BTW, there's a built-in library function for this: `collections.Counter()` – Barmar Mar 19 '21 at 18:30
2

Not `a_list[index]` but `a_list[row[index]]`. Or `return collections.Counter([row[index] for row in cars_data[1:]])` – azro Mar 19 '21 at 18:30

Trying to have python function return frequency table

0 Answers0