如何将列表中的元素与另一个元素是字典的列表中的元素进行比较？

Question

I have a list of strings, for example:

list1 = ['apple', 'orange', 'pear', 'peach']

and another list whose elements are dictionaries, like so:

list2 = [{'fruit': 'pear', 'size': 'big', 'rating': 7}, {'fruit': 'apple', 'size': 'small', 'rating': 6},{'fruit': 'peach', 'size': 'medium', 'rating': 7}, {'fruit': 'banana', 'size': 'big', 'rating': 9}]

For each element in list1, I need to determine if it appears as a value for any of the 'fruit' keys in list2's dictionaries. In this case, apple, pear and peach are all values of at least one 'fruit' key in list2, while orange is not. For each element in list1, how can I get a boolean true/false of whether it appears as a value for any 'fruit' key in list2?

Answer 1

You do some kind of for or list comprehension checking if the value is present in any of the elements of the second list , for example:

list1 = ['apple', 'orange', 'pear', 'peach']
list2 = [{'fruit': 'pear', 'size': 'big', 'rating': 7}, {'fruit': 'apple', 'size': 'small', 'rating': 6},{'fruit': 'peach', 'size': 'medium', 'rating': 7}, {'fruit': 'banana', 'size': 'big', 'rating': 9}]

booleans = [
    any(fruit == f_dict['fruit'] for f_dict in list2) for fruit in list1
]

print(booleans)
>>> [True, False, True, True]

Answer 2

This will create a dictionary for every value in list one where the value is a boolean which is true if the value is in list2's values

def ItemInList(name, list):
    for dic in list:
        for item in dic.values():
            if name == item:
                return True
    return False



list1 = ['apple', 'orange', 'pear', 'peach']
list2 = [{'fruit': 'pear', 'size': 'big', 'rating': 7}, {'fruit': 'apple', 'size': 'small', 'rating': 6},{'fruit': 'peach', 'size': 'medium', 'rating': 7}, {'fruit': 'banana', 'size': 'big', 'rating': 9}]
dict = {}

for item in list1:
    dict[item] = ItemInList(item, list2)

print(dict)

Answer 3

[ x in [y['fruit'] for y in list2] for x in list1]