Once you have the filtered dictionary, you can extract the key. Here’s how to do it: def find_key_by_value_comprehension(d, target_value): return [key for key, value in d.items() if value == target_value] my_dict = {'a': 1, 'b': 2, 'c': 3} result = find_key_by_...
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:returnkeyreturnNone 1. 2. 3. 4. 5. 上述代码定义了一个名为find_key_by_value的函数,该函数接受两个参数:dictionary表示要查找的字典,value表示要查找的值。函数通过遍历字典的键值对,找到与给定值相等的值,并返回对应...
We create a weekend dictionary using dictionary literal notation. The key-value pairs are enclosed by curly brackets. The pairs are separated by commas. The first value of a pair is a key, which is followed by a colon character and a value. The"Sun"string is a key and the"Sunday"string...
deffind_key(d, val):returnnext(keyforkey, valueind.items()ifvalue == val) d = {'Bob':1,'Mary':2,'Lisa':4,'Ken':5,'Vivi':2}print(find_key(d,2)) 输出: Mary 11、将两个列表组合为一个字典 这里有两个列表,第一个列表存放键,第二个列表存放值,要将这两个列表转换为一个字典。
A Python dictionary consists of a collection of key-value pairs, where each key corresponds to its associated value. In this example, "color" is a key, and "green" is the associated value.Dictionaries are a fundamental part of Python. You’ll find them behind core concepts like scopes and...
deffind_key_by_value(dictionary,value):forkey,valindictionary.items():ifval==value:returnkeyreturnNonestudent={'name':'Alice','age':18,'grade':'A'}key=find_key_by_value(student,'Alice')print(key)# 输出:name 1. 2. 3. 4.
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)
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 ...
Python 字典 in 操作符用于判断键是否存在于字典中,如果键在字典 dict 里返回 true,否则返回 false。而not in 操作符刚好相反,如果键在字典 dict 里返回 false,否则返回 true。语法in 操作符语法:key in dict参数key -- 要在字典中查找的键。返回值如果键在字典里返回true,否则返回false。