Delete an element from a dictionary Delete an element from a dictionary python python

Delete an element from a dictionary


The del statement removes an element:

del d[key]

Note that this mutates the existing dictionary, so the contents of the dictionary changes for anybody else who has a reference to the same instance. To return a new dictionary, make a copy of the dictionary:

def removekey(d, key):    r = dict(d)    del r[key]    return r

The dict() constructor makes a shallow copy. To make a deep copy, see the copy module.


Note that making a copy for every dict del/assignment/etc. means you're going from constant time to linear time, and also using linear space. For small dicts, this is not a problem. But if you're planning to make lots of copies of large dicts, you probably want a different data structure, like a HAMT (as described in this answer).


pop mutates the dictionary.

 >>> lol = {"hello": "gdbye"} >>> lol.pop("hello")     'gdbye' >>> lol     {}

If you want to keep the original you could just copy it.


I think your solution is best way to do it. But if you want another solution, you can create a new dictionary with using the keys from old dictionary without including your specified key, like this:

>>> a{0: 'zero', 1: 'one', 2: 'two', 3: 'three'}>>> {i:a[i] for i in a if i!=0}{1: 'one', 2: 'two', 3: 'three'}


matomo