Calculate food company sales for the year

I am working on a Python project where a food processing company is trying to calculate its total sales for the year. Python has to read from a text file where its divided into for categories split by commas.

The first category is the Type of product, which can be cereal, chocolate candy etc produced by the company.

The second category is the brand of the said product, for example, Kaptain Krunch for cereal or Coco Jam for chocolate. The third category is the sales for the last fiscal year (2014) and the last category is sales for this fiscal year(2015). Note that only sales for fiscal year 2015 are to be calculated. The 2014 has no use in this program but it is there.

Here is how the text file looks like, called product.txt:


Cereal,Magic Balls,2200,2344


Cereal,Kaptain Krunch,3300,3123


Cereal,Coco Bongo,1800,2100


Cereal,Sugar Munch,4355,6500


Cereal,Oats n Barley,3299,5400


Sugar Candy,Pop Rocks,546,982


Sugar Candy,Lollipop,1233,1544


Sugar Candy,Gingerbud,2344,2211


Sugar Candy,Respur,1245,2211


Chocolate,Coco Jam,3322,4300


Chocolate,Larkspur,1600,2200


Chocolate,Mighty Milk,1234,2235


Chocolate,Almond Berry,998,1233


Condiments,Peanut Butter,3500,3902


Condiments,Hot Sauce,1234,1560


Condiments,Jelly,346,544


Condiments,Spread,2334,5644

What we are looking to do is to add the sales for Fiscal year 2015 by products and then the total sales for everything in 2015.

The output should look something like this in the written text file:


Total sales for cereal in 2015 : {Insert total number here}


Total sales for Sugar Candy in 2015 : {Insert total number here}


Total sales for Chocolate in 2015 : {Insert total number here}


Total sales for Condiments in 2015 : {Insert total number here}




Total sales for the company in 2015: {Insert total for all the
products sold in 2015}

Along with that, it should also print the grand total on the Python run scr

Your code looks good, I have some minor suggestions:

Separate getting the data and outputting it

I would prefer reading something like this:

for product_info in product_informations(productfile):
    # Handle out-put of product_info

To separate concerns more clearly.

Use _ to signify un-used values

for category, brand, sales_lastyear, sales_thisyear in rows:
    categorycounts[category] += int(sales_thisyear)

The values brand and sales_lastyear are not used, so you do not need to give them a name:

for category, _, _, sales_thisyear in rows:
    categorycounts[category] += int(sales_thisyear)

Be explicit with file.write

If you want to write to a file, print will work just fine, but I suggest being the most explicit and using file.write.

This also helps separation of concerns because it forces formatting to be handled separately. (See str.format in the next paragraph)

Do not repeat yourself

print("Total sales for the company in 2015:", totalsales, file=reportfile)
    print("Total sales for the company in 2015:", totalsales)

Only the output destination changes.

You can either save the message in a variable:

sales_info = "Total sales for the company in 2015:{}".format(totalsales)

reportfile.write(sales_info)
print(sales_info)

Or use a loop:

for destination in (sys.stdout, reportfile):
    print("Total sales for the company in 2015:{}".format(totalsales), file=destination)

.format is also preferred over str + str and print(x, y) for its extensibility and readibility.

Indent in generator expressions

It is weird to see a for at the start of a line as part of a generator comprehension, because it looks like a loop statement, some indenting will clarify that it is part of a generator comprehension:

rows = (line.rstrip().split(',')
            for line in productfile if line.rstrip())

StackExchange Code Review Q#119043, answer score: 2