I have a dictionary where each keys have multiple values. I am trying to count the total number of values. For example:
key: 1, value: abc, bcd, egf
key: 2, value: asj,asfah,afhs,jhsafh
so, the total number of values are 3+4 = 7 What is the pythonic way to get this count. Thanks
How about:
sum(len(val) for val in dictionary.itervalues())
Note that this uses a generator instead of creating a temporary list of lengths.
You'll want to iterate through all the keys and values in the dictionary, finding the length of each set of values.
The following does uses a list comprehension to build a list of all these lengths, and then takes their sum:
sum([len(value) for key, value in my_dict.iteritems()])
If you want to be more efficient, you can replace for key, value in my_dict.iteritems() with for value in my_dict.itervalues() and a use generator expression as suggested by Cameron.
If you're sure that each value in the dict will be a list, then this works:
sum(len(val) for val in d.itervalues())
If not, a bit more care is required, and probably a bit more info. Strings, for example, also have a len (the count of characters in the string). You probably want strings to count as 1 entry, rather than a count proportional to length. If so, this less readable version works:
sum(1 if isinstance(val, basestring) else len(val) for val in d.itervalues())
sum(1 for value in value_iterable), and there are several ways you could check if the item was iterable or not, if you could have a list that was that heterogeneous (you shouldn't).dct['k'] = "wrong", instead ofdct['k'] = ["correct"]. guess it is a matter of discipline.