items(): if value == target_value: return key return None my_dict = {'a': 1, 'b': 2, 'c': 3} result = find_key_by_value(my_dict, 2) Output: b In this example, we define a function called find_key_by_value that takes a dictionary and a target value as arguments. ...
my_dict={'a':1,'b':2,'c':3,'d':1}value_to_find=2key=find_key_by_value(my_dict,value_to_find)ifkeyisnotNone:print(f"The key corresponding to value{value_to_find}is{key}.")else:print(f"The value{value_to_find}does not exist in the dictionary.") 1. 2. 3. 4. 5. 6...
def find_key_by_value(dictionary, search_value): for key, value in dictionary.items(): if value == search_value: return key rAIse ValueError("Value does not exist in the dictionary") 三、创建反向字典 当你需要频繁地通过值来查找键时,可以考虑创建一个反向字典,其中值作为键,原始键作为值。这样...
deffind_key_by_value(dictionary, value): forkey, valindictionary.items(): ifval==value: returnkey returnNone # 示例用法 my_dict={'a':1,'b':2,'c':3,'d':2} search_value=2 result=find_key_by_value(my_dict, search_value) ifresult: print(f"找到了值 {search_value} 对应的键:{r...
To sort a dictionary by its values in Python, you can use the sorted function with a lambda function as the key argument. A Python dictionary is a built-in data type that represents a collection of key-value pairs
# 创建一个示例字典dictionary={'apple':1,'banana':2,'orange':3,'grape':2}# 调用方法一:遍历字典key=find_key_by_value(dictionary,2)print(f"方法一:遍历字典,键为{key}")# 输出:方法一:遍历字典,键为 banana# 调用方法二:使用列表推导式key=find_key_by_value(dictionary,2)print(f"方法二:使...
If you ever need to find the minimum and maximum value stored in a dictionary, then you can use the built-in min() and max() functions: Python >>> computer_parts = { ... "CPU": 299.99, ... "Motherboard": 149.99, ... "RAM": 89.99, ... "GPU": 499.99, ... "SSD...
In Python, the dictionary class doesn't have any provision to sort items in its object. Hence, some other data structure, such as the list has to be used to be able to perform sorting. To begin with, our test data is following dictionary object having names and marks of students. ...
Then, theforloop is utilized to find keys for each of the values present by iterating over the sorted values. Thekey:valuepairs that are found are then represented in the sorted order through a fresh dictionary. We should note that by using thesorted()function on the dictionary, we cannot...
In simple terms, a Python dictionary can store pairs of keys and values. Each key is linked to a specific value. Once stored in a dictionary, you can later obtain the value using just the key. For example, consider the Phone lookup, where it is very easy and fast to find the phone ...