Deleting a few list items inside of dictionary

问题

Hi, I have a dictionary:

phone = {"first":100,"second":200,"third":[10,12,5,38],"fourth":400}

Let' say I want to remove the 12 and 5 from from "phone" dictionary. Is there a way to do that using a "del" function?

I know how to do this, using a .remove()

phone["third"].remove(12)
phone["third"].remove(5)

but I was wondering if it is possible to do it using the del()? Thank you.

EDIT: For all those replies concentrating on "del uses index, remove uses the exact value", I am redefining my question:

I want to delete the indexes 1 and 2 in the list representing the third key-value item in "phone" dictionary. How can I do that?

回答1:

You have to do this by index rather than value:

>>> phone = {"first":100,"second":200,"third":[10,12,5,38],"fourth":400}
>>> del(phone["third"][1:3])
>>> phone
{'second': 200, 'fourth': 400, 'third': [10, 38], 'first': 100}

This deletes elements in position 1 and 2 in the list.

回答2:

You can use del() or you can re-create the list by filtering it:

>>> phone = {"first":100,"second":200,"third":[10,12,5,38],"fourth":400}
>>> phone['third'] = [x for x in phone['third'] if x not in (12,5)]
>>> phone
{'second': 200, 'fourth': 400, 'third': [10, 38], 'first': 100}

回答3:

Access values of the phone dictionary, Remove items of the List .

other answer - try get the item (key, value) containing data you want to change. remove it from dictionary. modify values (list) of this item. and then add it to dictionary

回答4:

You can treat phone["third"] as a list since that is what it evaluates to. For instance, if you know the indexes of the items you want to remove you can do:

phone["third"][1:3]=[]

del phone["third"][1:3]

回答5:

http://docs.python.org/2/tutorial/datastructures.html#the-del-statement del is a way to delete by index not value, however you can search the index first if you want. Better to use remove if you want to delete by value.

To delete the element at index 1 and 2

>>> phone = {"first":100,"second":200,"third":[10,12,5,38],"fourth":400}
>>> del phone["third"][1]
>>> del phone["third"][2]
>>> phone
{'second': 200, 'fourth': 400, 'third': [10, 5], 'first': 100}

来源：https://stackoverflow.com/questions/16376471/deleting-a-few-list-items-inside-of-dictionary

标签

python

list

dictionary

del