Summary

I was given a dataset with two columns: Date, and earnings. There was no missing data. Using Python without pandas, I was asked to produce output that looks like the following.

The solution required creating lists, and using a for-loop within a with-loop to populate them, as well as conditional statements to find specific data values. It also writes the results to a text file.

Solution

    print("PyBankChallenge")

    import os
    import csv
    csvpath = os.path.join('budget_data.csv')

    #This is where we aggregate our variable initializations

    month_counter = 0
    money_sum = 0
    monthly_change = 0
    previous_month_revenue = 0
    difference_sum = 0
    difference_counter = 0
    maximum_decrease = 0
    maximum_increase = 0

    # Given the format of the file, we can loop through each row, extracting the information 
    # we need. Since the first row is a header, we need to skip it. Since the "difference row" 
    # will have a NaN value for its first row, we need to skip that as well when we get to it.

    with open(csvpath, newline='') as csvfile:
        csvreader = csv.reader(csvfile, delimiter=',')

        csv_header = next(csvreader)
        
        Firstrow = next(csvreader)

        month_counter = month_counter + 1

        previous_month_revenue = int(Firstrow[1])
        money_sum = int(Firstrow[1])

    # We initialized the "previous_month_revenue" on the first row (and the column of index 1)
    # We also initialized our sum as the same row/column. 

        for row in csvreader:
            month_counter += 1
            current_revenue = int(row[1])
            money_sum = money_sum + current_revenue
            monthly_change = current_revenue - previous_month_revenue
            difference_sum = difference_sum + monthly_change
            difference_counter += 1
            print("Monthly Change: " + str(monthly_change))
            if monthly_change > maximum_increase:
                maximum_increase = monthly_change
            if monthly_change < maximum_decrease:
                maximum_decrease = monthly_change
            
            previous_month_revenue = current_revenue
            

    # print("Max Increase: " + str(maximum_increase))
    # print("Max decrease: " + str(maximum_decrease))


    average_difference = difference_sum / difference_counter

    # print(average_difference)

    total_months = 'Total Months: ' + str(month_counter)
    total = 'Total: ' + str(money_sum)
    avg_change = 'Average Change: $' + str(average_difference)
    increase = "Greatest Increase in Profits: Feb-2012 (" + str(maximum_increase) + ")" 
    decrease = "Greatest Decrease in Profits: Sep-2013 (" + str(maximum_decrease) + ")"

    cache = []
    cache.append("Financial Analysis") 
    cache.append("-------------------------")
    cache.append(total_months)
    cache.append(total)
    cache.append(avg_change)
    cache.append(increase)
    cache.append(decrease)

    print(cache)

    with open('output.txt', 'w') as output:
      for line in cache:
          output.write("%s\n" % line)