Assignment 3 Solution

Problem 1: The Weird Widget Company of New York has several stores in New York. Each evening, the corporate office in midtown Manhattan receives sales figures from each store in a list of tuples. Each tuple contains two elements, (store, sales).

 

Write a program that prints the total sales and the average sales for the day. Use a for loop to calculate the total sales and the average sales (try not to use any external libraries!).

 

Example:

 

daily_sales  = [(‘A',150234.22),('B',73232.90),('C',110493.29),('D',

231965.64),('E',66398.58)] Your program should print:

Total sales today: $632324.63

Average sales today: $126464.93

 

What you need:

 

1. set total_sales  to 0

2. for: use a for loop to iterate through the daily_sales  list adding the second value of each tuple to total_sales  at each iteration

3. len: after the end of the loop, calculate the average. Use the len function to figure out the number of data items (for the average)

4. print formatting:  print the results. You’ll need to format the average to two decimal places and add the $ sign in the front of the numbers.

 

 

 

Problem 2: The corporate office of the Weird Widget Company of New York also has data on budgeted sales for each store. Budgeted Sales data is stored in a dict with store identifiers  as the key. Write a program that prints out the store identifiers  of stores that have underperformed or over performed their budget by more than x%.

 

Example:

 

daily_sales  = [(‘A’,150234.22),('B',73232.90),('C',110493.29),('D',

231965.64),('E',66398.58)]

budgeted_sales = {‘A’:140296.00,’B’:103981.00,’C’:80452.00,’D':

200900.00,'E':90000.00}

performance_threshold = 20

Your program should print:

 

 

Store
B
over
or
underperformed
its
budget
Store
C
over
or
underperformed
its
budget
Store
E
over
or
underperformed
its
budget
 

What you need:

 

1. for: a for loop to iterate over the daily_sales  list

2. len: for the number of tuples in daily_sales

3. if: to compare percent over or under budget for each store

4. abs: since we’re interested in the magnitude of performance difference and are ignoring the sign

 

 

 

 

Problem 3: An equity hedge fund stores its portfolio of equities in a list of tuples. Each tuple contains four elements: the ticker, number of shares, cost basis, and the current price. You are hired to help

the fund analyze its portfolio and you decide to write a function that returns useful information.  You need to do the following:

 

1. Write a function under_water  that takes a tuple (ticker,shares,cost,price) as an argument and returns True if the position is losing money and False otherwise.

2. Write a function above_water  that takes a tuple (ticker,shares,cost,price) as an argument and returns False if the position is under water and True otherwise.

3. Write a function get_data that takes two arguments, a portfolio x and a function y. The function returns two values: the number of items in x for which the function y returns True and the total unrealized profit on the portfolio

4. A position is a losing position if:

 

shares * (price - cost) < 0

 

 

 

Example:

 

portfolio = [(‘AAPL',-100,110.33,93.79),('IONS',700,11.22,33.33), ('GS',400,189.72,150.70),('SBUX',300,44.73,53.72)]

 

under_water((‘AAPL’,-100,110.33,93.79)) should return False under_water((‘GS’,400,189.72,150.70)) should return True

 

above_water((‘AAPL’,-100,110.33,93.79)) should return True above_water((‘GS’,400,189.72,150.70)) should return False

get_data(portfolio,under_water) should return (1, 4219.999999999996)

get_data(portfolio,above_water) should return (3, 4219.999999999996) What you need:

1. def: You need to write two functions. Make sure you use return and you don’t need to print anything.

2. pass a function as an argument: Look at the example we did in class on how to pass functions as arguments and then how to use the function once you’ve passed it.

3. return x,y: A function can return more than one value. Just separate the values using commas.