显示嵌套字典的条目

Question

I have a nested dict that looks like this:

17733124060: {'PhoneOwner': u'Bob', 'Frequency': 0}, 
18444320737: {'PhoneOwner': u'Sarah', 'Frequency': 1}, 
18444320742: {'PhoneOwner': u'Jane', 'Frequency': 0}

I want to be able to run a query that presents back the key 17733124060 and PhoneOwner Bob if the frequency is 0.

So far I have:

for phoneNumber, PhoneOwner, Frequency in dict.iteritems():
    if Frequency == 0:
    print phoneNumber + PhoneOwner

But when I run this, I get an error:

for phoneNumber, PhoneOwner, Frequency in phoneNumberDictionary.iteritems():
ValueError: need more than 2 values to unpack

What am I missing where?

Answer 1

You could use a list comprehension to first build a list of matching entries and then print them as follows:

my_dict = {
    17733124060: {'PhoneOwner': u'Bob', 'Frequency': 0}, 
    18444320737: {'PhoneOwner': u'Sarah', 'Frequency': 1}, 
    18444320742: {'PhoneOwner': u'Jane', 'Frequency': 0}}

zero_freq = [(k, v['PhoneOwner']) for k, v in my_dict.items() if v['Frequency'] == 0]

for number, owner in zero_freq:
    print number, owner

This would display the following:

17733124060 Bob
18444320742 Jane

Also, just in case, don't name your dictionary dict as this a builtin Python function.

Answer 2

for phoneNumber, PhoneOwner, Frequency in dict.iteritems():

You are trying to unpack two values ( dict.itertimes() returns 2-tuples) into 3 variables. Instead you should first iterate over the outer dict, then evaluate the nested dict:

for phoneNumber, inner_dict in phonenumbers.iteritems():
    if inner_dict['Frequency'] == 0:
        print str(phoneNumber) + inner_dict['PhoneOwner']

Answer 3

Another approach could be using the built-in method, filter , where you filter your dictionary according to your condition ( sub_d[Frequency]==0 ), this way:

>>> d
{17733124060L: {'Frequency': 0, 'PhoneOwner': u'Bob'}, 18444320742L: {'Frequency': 0, 'PhoneOwner': u'Jane'}, 18444320737L: {'Frequency': 1, 'PhoneOwner': u'Sarah'}}
>>> for i in filter(lambda s:d[s]['Frequency']==0, d):
    print '%d %s' % (i, d[i]['PhoneOwner'])


17733124060 Bob
18444320742 Jane