CIS_File_Invoice

Question

Create a program that summarizes the total invoice for the countries Germany, Norway, Belgium, Canada, USA, France, Ireland, and United Kingdom plus indicate how many invoices for each country and the average invoice amount for each country.

The output report will be formatted in column format and consist of the following with headers. (please note this is an example of the formatted output, not an actual result from the program)

Country          Num_Invoices            Avg$/Invoice Total Amount $

USA                           10                               15.50              155.00

Peru                            3                                 4.25                12.75

Formatting round any calculations to 2 decimal places, the output should contain at the most 2 decimal locations (no more or no less) for floats.

Answer 1

Hey Andrew!

A group by request like this fits well as a pandas DataFrame to represent and manipulate the data.

What I imagine the data to look like:

| country | invoice_amount |

| Peru | 1200.09 |

| Germany | 500.0 |

| Germany | 6712.45 |

If data like this is read into a Pandas DataFrame with "country" and "invoice_amount" as the columns (invoice_df below), we can perform a GroupBy method on the data to aggregate the invoice amounts by country

invoices_by_country = (invoice_df.groupby('country')

.agg({'invoice_amount': ['count', 'mean', 'sum']})

.rename(columns={'count':'Num_Invoices',

'mean': 'Avg_Invoice_Total',

'sum': 'Total_Amount'})

.round(decimals=2))

Now, invoiced_by_country should look just like the table required. For every country, we get the count of invoices ('Num_Invoices'), the average value of an invoice ('Avg_Invoice_Total') and the summation of all of the invoice values ('Total_Amount')

As a note though, this function rounds the data to two decimal places. But, I'm confused with the wording above. It says to both round to "at most 2" decimal places and also "no more and no less" than 2 places for decimals. These are rather different requests. But, the code as shown, will not show extra zeros at the end of a number, following the "at most 2" rule. So, for example, 2.1 will be represented as 2.1 instead of 2.10.