在字典中，如何从具有多个值的键中删除一个值？ 蟒蛇

Question

from collections import OrderedDict

def main():
    dictionary = OrderedDict()
    dictionary["one"] = ["hello", "blowing"]
    dictionary["two"] = ["frying", "goodbye"]

    for key in dictionary:
        print key, dictionary[key]

    user_input = raw_input("REMOVE BUILDINGS ENDING WITH ING? Y/N")
    if user_input == ("y"):
        print ""
        for key in dictionary:
            for x in dictionary[key]:
                if ("ING") in x or ("ing") in x:
                    del dictionary[key][x]

    print ""

    for key in dictionary:
        print key, dictionary[key]

main()

I am attempting to remove any item with "ing" in it from all keys within a dictionary, example "blowing" from the key "one" and "frying" from the key "two".

The resulting dictionary would go from this:

one ['hello', 'blowing'], two ['frying', 'goodbye']

to this:

one ['hello'], two ['goodbye']

Answer 1

dict comprehension.

return {x : [i for i in dictionary[x] if not i.lower().endswith('ing')] for x in dictionary}

Edited to replace values ending with 'ing' with 'removed'

return {x : [i if not i.lower().endswith('ing') else 'removed' for i in dictionary[x]] for x in dictionary}

Answer 2

You can do this in an immutable fashion (ie, without mutating the original dict) by using a dict comprehension :

>>> d = {'one': ['hello', 'blowing'], 'two': ['frying', 'goodbye']}
>>> {k: [w for w in v if not w.lower().endswith('ing')] for k, v in d.items()}
{'one': ['hello'], 'two': ['goodbye']}

Answer 3

Try this:

>>> collections.OrderedDict({key:filter(lambda x:not x.endswith('ing'), value) for key,value in dictionary.items()})
OrderedDict([('two', ['goodbye']), ('one', ['hello'])])

Answer 4

{key: [ele for ele in val if not ele.lower().endswith('ing')] for key, val in d.items()}

Explanation:

Start from the right,

• d is the dictionary, it stores <key, [val]>

• for each key, val in d we do the following,

• [ele for ele in val if not ele.lower().endswith('ing')] means for every element( ele ) in list( val ) we perform the operations :

  • convert each string to lower case
  • check if it ends-with `ing'
  • then if none of these( if not ) then get ele

• Then you just print { key: [ele1, ele2, ..] , .. } .

Answer 5

You were trying to delete with string index not int position reference. Here is the modified code:

from collections import OrderedDict

def main():
    dictionary = OrderedDict()
    dictionary["one"] = ["hello", "blowing"]
    dictionary["two"] = ["frying", "goodbye"]

    for key in dictionary:
        print key, dictionary[key]

    user_input = raw_input("REMOVE BUILDINGS ENDING WITH ING? Y/N")
    if user_input == ("y"):
        print ""
        for key,value in dictionary.iteritems():
            for i,x  in enumerate(value):
                if ("ING") in x or ("ing") in x:
                    del dictionary[key][i]

    print ""

    for key in dictionary:
        print key, dictionary[key]

main()