How to delete entire dictionary in python

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Removing Items from a Dictionary
How do you clear an entire dictionary in Python?
Can we delete a dictionary in Python?
What is a correct syntax to delete all content in a dictionary?
How do I get rid of a dictionary?

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The clear() method removes all items from the dictionary.

Syntax:

dict.clear()

Parameters:

The clear() method doesn't take any parameters.

Returns:

The clear() method doesn't return any value.

Examples:

Input : d = {1: "geeks", 2: "for"}
        d.clear()
Output : d = {}

Error:

As we are not passing any parameters there
is no chance for any error.

text = {1: "geeks", 2: "for"}

text.clear()

print('text =', text)

Output:

text = {}

How is it different from assigning {} to a dictionary?
Please refer the below code to see the difference. When we assign {} to a dictionary, a new empty dictionary is created and assigned to the reference. But when we do clear on a dictionary reference, the actual dictionary content is removed, so all references referring to the dictionary become empty.

text1 = {1: "geeks", 2: "for"}

text2 = text1

text1.clear()

print('After removing items using clear()')

print('text1 =', text1)

print('text2 =', text2)

text1 = {1: "one", 2: "two"}

text2 = text1

text1 = {}

print('After removing items by assigning {}')

print('text1 =', text1)

print('text2 =', text2)

Output:

After removing items using clear()
text1 = {}
text2 = {}
After removing items by assigning {}
text1 = {}
text2 = {1: 'one', 2: 'two'}

Removing Items from a Dictionary

There are several methods to remove items from a dictionary:

Example

The pop() method removes the item with the specified key name:

thisdict = {
  "brand": "Ford",
  "model": "Mustang",
  "year": 1964
}
thisdict.pop("model")
print(thisdict)

Try it Yourself »

Example

The popitem() method removes the last inserted item (in versions before 3.7, a random item is removed instead):

thisdict = {
  "brand": "Ford",
  "model": "Mustang",
  "year": 1964
}
thisdict.popitem()
print(thisdict)

Try it Yourself »

Example

The del keyword removes the item with the specified key name:

thisdict = {
  "brand": "Ford",
  "model": "Mustang",
  "year": 1964
}
del thisdict["model"]
print(thisdict)

Try it Yourself »

Example

The del keyword can also delete the dictionary completely:

thisdict = {
  "brand": "Ford",
  "model": "Mustang",
  "year": 1964
}
del thisdict
print(thisdict) #this will cause an error because "thisdict" no longer exists.

Try it Yourself »

Example

The clear() keyword empties the dictionary:

thisdict = {
  "brand": "Ford",
  "model": "Mustang",
  "year": 1964
}
thisdict.clear()
print(thisdict)

Try it Yourself »

There're a lot of nice answers, but I want to emphasize one thing.

You can use both dict.pop() method and a more generic del statement to remove items from a dictionary. They both mutate the original dictionary, so you need to make a copy (see details below).

And both of them will raise a KeyError if the key you're providing to them is not present in the dictionary:

key_to_remove = "c"
d = {"a": 1, "b": 2}
del d[key_to_remove]  # Raises `KeyError: 'c'`

and

key_to_remove = "c"
d = {"a": 1, "b": 2}
d.pop(key_to_remove)  # Raises `KeyError: 'c'`

You have to take care of this:

by capturing the exception:

key_to_remove = "c"
d = {"a": 1, "b": 2}
try:
    del d[key_to_remove]
except KeyError as ex:
    print("No such key: '%s'" % ex.message)

and

key_to_remove = "c"
d = {"a": 1, "b": 2}
try:
    d.pop(key_to_remove)
except KeyError as ex:
    print("No such key: '%s'" % ex.message)

by performing a check:

key_to_remove = "c"
d = {"a": 1, "b": 2}
if key_to_remove in d:
    del d[key_to_remove]

and

key_to_remove = "c"
d = {"a": 1, "b": 2}
if key_to_remove in d:
    d.pop(key_to_remove)

but with pop() there's also a much more concise way - provide the default return value:

key_to_remove = "c"
d = {"a": 1, "b": 2}
d.pop(key_to_remove, None)  # No `KeyError` here

Unless you use pop() to get the value of a key being removed you may provide anything, not necessary None. Though it might be that using del with in check is slightly faster due to pop() being a function with its own complications causing overhead. Usually it's not the case, so pop() with default value is good enough.

As for the main question, you'll have to make a copy of your dictionary, to save the original dictionary and have a new one without the key being removed.

Some other people here suggest making a full (deep) copy with copy.deepcopy(), which might be an overkill, a "normal" (shallow) copy, using copy.copy() or dict.copy(), might be enough. The dictionary keeps a reference to the object as a value for a key. So when you remove a key from a dictionary this reference is removed, not the object being referenced. The object itself may be removed later automatically by the garbage collector, if there're no other references for it in the memory. Making a deep copy requires more calculations compared to shallow copy, so it decreases code performance by making the copy, wasting memory and providing more work to the GC, sometimes shallow copy is enough.

However, if you have mutable objects as dictionary values and plan to modify them later in the returned dictionary without the key, you have to make a deep copy.

With shallow copy:

def get_dict_wo_key(dictionary, key):
    """Returns a **shallow** copy of the dictionary without a key."""
    _dict = dictionary.copy()
    _dict.pop(key, None)
    return _dict


d = {"a": [1, 2, 3], "b": 2, "c": 3}
key_to_remove = "c"

new_d = get_dict_wo_key(d, key_to_remove)
print(d)  # {"a": [1, 2, 3], "b": 2, "c": 3}
print(new_d)  # {"a": [1, 2, 3], "b": 2}
new_d["a"].append(100)
print(d)  # {"a": [1, 2, 3, 100], "b": 2, "c": 3}
print(new_d)  # {"a": [1, 2, 3, 100], "b": 2}
new_d["b"] = 2222
print(d)  # {"a": [1, 2, 3, 100], "b": 2, "c": 3}
print(new_d)  # {"a": [1, 2, 3, 100], "b": 2222}

With deep copy:

from copy import deepcopy


def get_dict_wo_key(dictionary, key):
    """Returns a **deep** copy of the dictionary without a key."""
    _dict = deepcopy(dictionary)
    _dict.pop(key, None)
    return _dict


d = {"a": [1, 2, 3], "b": 2, "c": 3}
key_to_remove = "c"

new_d = get_dict_wo_key(d, key_to_remove)
print(d)  # {"a": [1, 2, 3], "b": 2, "c": 3}
print(new_d)  # {"a": [1, 2, 3], "b": 2}
new_d["a"].append(100)
print(d)  # {"a": [1, 2, 3], "b": 2, "c": 3}
print(new_d)  # {"a": [1, 2, 3, 100], "b": 2}
new_d["b"] = 2222
print(d)  # {"a": [1, 2, 3], "b": 2, "c": 3}
print(new_d)  # {"a": [1, 2, 3, 100], "b": 2222}

How do you clear an entire dictionary in Python?

The clear() method removes all items from the dictionary..

Syntax: dict.clear().

Parameters: The clear() method doesn't take any parameters..

Returns: The clear() method doesn't return any value..

Examples: Input : d = {1: "geeks", 2: "for"} d.clear() Output : d = {}.

Error: ... .

Output: text = {}.

Can we delete a dictionary in Python?

You can use the following methods to remove items from a dictionary in Python: The del keyword. The clear() method. The pop() method.

What is a correct syntax to delete all content in a dictionary?

clear() Syntax Here, clear() removes all the items present in the dictionary.

How do I get rid of a dictionary?

To remove a key from a dictionary in Python, use the pop() method or the “del” keyword. Both methods work the same in that they remove keys from a dictionary. The pop() method accepts a key name as argument whereas “del” accepts a dictionary item after the del keyword.

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How to delete entire dictionary in python

Removing Items from a Dictionary

Example

Example

Example

Example

Example

How do you clear an entire dictionary in Python?

Can we delete a dictionary in Python?

What is a correct syntax to delete all content in a dictionary?

How do I get rid of a dictionary?

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