How do I print out just the values of keys in a dictionary?

Question

I'm trying to create a function that prints out just the value of the key given in the parameter. But it isn't quite doing what I want it to do. Please have a look at my code and see where I'm wrong? Thanks

list = {
    "David": 42,
    "John": 11,
    "Jack": 278
}

def get_marks(student_name):
    for marks in list.items():
        print(marks)

get_marks("David")

@Rawing It's a better pratice to use the `get` function of the dict, to prevent you from getting a key error if the element does not exist — HolyDanna, Jul 25 '16 at 13:54
Possible duplicate of http://stackoverflow.com/questions/5904969/python-how-to-print-a-dictionarys-key — Moon Cheesez, Jul 25 '16 at 13:55
@HolyDanna That's an odd statement. What if I want to get a KeyError? — Aran-Fey, Jul 25 '16 at 13:55
@Rawing the `get` function allows you to set a default value if no value is found. — Moon Cheesez, Jul 25 '16 at 13:56
@HolyDanna you should provide a bit more background with a statement like that. `list[student_name]` is often preferred. — Jack Ryan, Jul 25 '16 at 13:56
OT, but don't use the variable name `list` for anything, let alone for a dictionary. — DeepSpace, Jul 25 '16 at 14:02
Don't name your list `list`. This rebinds the list function to your list. It can make things break — joel goldstick, Jul 25 '16 at 14:02

score 0 · Answer 1 · answered Jul 25 '16 at 13:53

0

You are trying this:

def get_marks(student_name):
    print(list.get(student_name))

answered Jul 25 '16 at 13:53

okuznetsov

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Moses Koledoye · Answer 2 · 2016-07-25T13:58:47.240

0

You can access the value at a key using my_dict[student_name] but using the get method of the dictionary is much safer as it returns None when the key is not found:

def get_marks(student_name):
    print my_dict.get(student_name)

I have renamed your dictionary from list to my_dict to avoid shadowing the builtin list class.

edited Jul 25 '16 at 13:58

answered Jul 25 '16 at 13:53

Moses Koledoye

77,341
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score 0 · Answer 3 · answered Jul 25 '16 at 13:55

0

list = {
"David": 42,
"John": 11,
"Jack": 278
}

def get_marks(student_name):
    print list[student_name]

get_marks("David")

answered Jul 25 '16 at 13:55

khelili miliana

3,730
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score 0 · Answer 4 · answered Jul 25 '16 at 14:01

You can either use the get() method of the dictionary like so:

def get_marks(student_name):
    return list.get(student_name)

or you can just use basic dictionary access (Section 5.5) and handle missing keys on your own:

def get_marks(student_name):
    if student_name in list:
        return list[student_name]
    else:
        #Key not in dict, do something

How do I print out just the values of keys in a dictionary?

4 Answers4