Question

Fill in the function shopSmart(orders,shops) in shopSmart.py, which takes an orderList (like the kind passed in to FruitShop.getPriceOfOrder) and a list of FruitShop and returns the FruitShop where your order costs the least amount in total. Don't change the file name or variable names, please. Note that we will provide the shop.py implementation as a "support" file, so you don't need to submit yours. Run python autograder.py until question 3 passes all tests and you get full marks. Each test will confirm that shopSmart(orders,shops) returns the correct answer given various possible inputs. For example, with the following variable definitions: orders1 = [('apples',1.0), ('oranges',3.0)] orders2 = [('apples',3.0)] dir1 = {'apples': 2.0, 'oranges':1.0} shop1 = shop.FruitShop('shop1',dir1) dir2 = {'apples': 1.0, 'oranges': 5.0} shop2 = shop.FruitShop('shop2',dir2) shops = [shop1, shop2] test_cases/q3/select_shop1.test tests whether:

Answer 1

Answer:

def shopSmart(orderList, fruitShops):  #function definition

   shop = fruitShops[0] #sets the shop to first item of fruitShops list

   leastAmount = shop.getPriceOfOrder(orderList)  #passes the orderList to getPriceOfOrder method which returns the total cost and saves it to leastAmount

   for fruitshop in fruitShops[1:]:  #iterates through the shops in fruitShops list

    cost = fruitshop.getPriceOfOrder(orderList)  #checks each cost or order using getPriceOfOrder method and passing orderList to it

    if cost < leastAmount:  #checks where order costs the least amount in total

     shop = fruitshop  #sets the FruitShop where order costs the least amount in total

     leastAmount = cost  #sets that minimum of order cost to leastAmount

   return shop #returns the FruitShop where order costs the least amount in total

Explanation:

Here are the getPriceOfOrder() and getName()) methods that is used in the above method.

def getPriceOfOrder(self, orderList):        

       totalCost = 0.0              

       for fruit, numPounds in orderList:

           costPerPound = self.getCostPerPound(fruit)

           if costPerPound != None:

               totalCost += numPounds * costPerPound

       return totalCost

def getName(self):

       return self.name

Here is the main program:

orders = [('apples',1.0), ('oranges',3.0)]

dir1 = {'apples': 2.0, 'oranges':1.0}

shop1 =  shop.FruitShop('shop1',dir1)

dir2 = {'apples': 1.0, 'oranges': 5.0}

shop2 = shop.FruitShop('shop2',dir2)

shops = [shop1, shop2]

print("For orders ", orders, ", the best shop is", shopSmart(orders, shops).getName())

orders = [('apples',3.0)]

print("For orders: ", orders, ", the best shop is", shopSmart(orders, shops).getName())

Notice that the statement:

print("For orders ", orders, ", the best shop is", shopSmart(orders, shops).getName())

has orders list which is:

[('apples',1.0), ('oranges',3.0)]

and it has shops which is a list containing two shops:

shops = [shop1, shop2]

It also calls method shopSmart by passing orders and these two shops to get the shop where the order costs the least amount in total. It has a for loop that iterates through each shop and check the orders using getPriceOfOrder method to determine at which shop the order costs the least amount in total. When the least amount is found it is set to the variable leastAmount and the shop corresponding to this order which has least amount is set to shop variable. At the end this shop is returned by the function. getName() method is used in the main program to get the name of the shop with least amount of order cost. So above print statement gives the following output:

For orders  [('apples', 1.0), ('oranges', 3.0)] , the best shop is shop1    

The entire program along with its output is attached.