3 min read•june 24, 2024
Python dictionaries are versatile data structures that store . They're mutable, allowing dynamic modifications like adding, updating, or removing items. This flexibility makes dictionaries ideal for organizing and accessing data efficiently.
Dictionaries offer various methods for manipulation and . You can access values using keys, add new pairs, remove items, and iterate through components. Understanding these operations is crucial for effective usage Python programming.
dictionary[key]
student["name"]
returns "John")[KeyError](https://www.fiveableKeyTerm:KeyError)
exceptiondictionary[key] = new_value
[get()](https://www.fiveableKeyTerm:get())
method provides an alternative way to access values dictionary.get(key, default_value)
default_value
(None
by default)dictionary[new_key] = value
student["age"] = 25
adds "age" key)student["name"] = "Jane"
updates "name" value)[update()](https://www.fiveableKeyTerm:update())
method merges another dictionary or an iterable of key-value pairs into the dictionary
dictionary.update(other_dict)
merges other_dict
into dictionary
dictionary.update(iterable)
merges key-value pairs from iterable
into dictionary
[del](https://www.fiveableKeyTerm:del)
statement removes a specific key-value pair from the dictionary del dictionary[key]
del student["age"]
removes "age" key)KeyError
if the key doesn't exist[pop()](https://www.fiveableKeyTerm:pop())
method removes a key-value pair and returns the corresponding value value = dictionary.pop(key, default_value)
age = student.pop("age")
removes and returns the "age" value)default_value
if the key doesn't exist (raises KeyError
if default_value
not provided)[popitem()](https://www.fiveableKeyTerm:popitem())
method removes and returns an arbitrary key-value pair as a tuple (key, value) = dictionary.popitem()
[clear()](https://www.fiveableKeyTerm:clear())
method removes all key-value pairs, emptying the dictionary dictionary.clear()
[keys()](https://www.fiveableKeyTerm:keys())
method returns a view object containing all the dictionary keys for key in dictionary.keys():
for key in dictionary:
achieves the same result[values()](https://www.fiveableKeyTerm:values())
method returns a view object containing all the dictionary values for value in dictionary.values():
[items()](https://www.fiveableKeyTerm:items())
method returns a view object containing all the key-value pairs as tuples for key, value in dictionary.items():
for name, grade in student.items():
)