python Dictionary for printing inventory if value is less than input

user_11364486 0
Viewed 820

A computer store manages its laptop inventory by using Python dictionaries. Each dictionary entry has the string name of a specific computer laptop model as a key and its integer quantity in inventory as its corresponding value.

An example:

d = {"MS Surface":47, "HP Laptop Probook":144, "MacBook Pro":23, "Dell Laptop XPS": 10, "Asus Chromebook": 20}

Define a function low_inventory(laptop_dict, threshold) which returns a list of the names of all entries in laptop inventory laptop_dict whose quantities are less than (<) the int threshold.

Example: calling your function as total_items(d,47) should return :

['MacBook Pro', 'Dell Laptop XPS', 'Asus Chromebook']

def low_inventory(laptop_dict, threshold):
    for akey in laptop_dict.keys():
        if laptop_dict[akey] < threshold:
                ----

Could you please suggest how to do this. I am new to python and struggling with output.

python-3.x python
3 Answers

You need to return a list, so you could start by defining one. Something like: 

low_inv = []

Then in your loop append() the key (which is the name of the computer in this case) to that list if the inventory is low. Then return it:

d = {"MS Surface":47, "HP Laptop Probook":144, "MacBook Pro":23, "Dell Laptop XPS": 10, "Asus Chromebook": 20}

def total_items(laptop_dict, threshold):
    low_inv = []                           # new list
    for akey in laptop_dict.keys():
        if laptop_dict[akey] < threshold:
            low_inv.append(akey)           # append to it
    return low_inv                         # return it

total_items(d,47)

#['MacBook Pro', 'Dell Laptop XPS', 'Asus Chromebook']

This can also be done as a list comprehension, which creates a list in one go without the explicit loop:

def total_items(laptop_dict, threshold):
    return [akey for akey, inv in laptop_dict.items() if inv < threshold]
user_38746230

You can use d.items() to iterate over the dictionary given the key and value. Try something like this:

def low_inventory(laptop_dict, threshold):
    low = []
    for key, value in laptop_dict.items():
        if value < threshold:
            low.append(key)
    return low
user_69330390
user_19534200
Related