如何用python计算列表中的单词列表

Arif Shahriar • 5 年前 • 1540 次点击

我有以下清单:

fruits = [âappleâ, âbananaâ, âgrapeâ, âkiwiâ, âbananaâ, âappleâ, âappleâ, âwatermelonâ, âkiwiâ, âbananaâ, âappleâ,]

现在我必须开发一个名为count_the_fruits的函数,它将把一个水果列表和一个名为words的变量参数列表作为参数。函数应该使用字典理解来创建单词字典(键)及其对应的计数(值)。

words = ["apple", "banana", "kiwi"]

{apple: 4, 'banana': 3, 'kiwi': 2}

任何帮助都将不胜感激。谢谢!

Python社区是高质量的Python/Django开发社区
本文地址：http://www.python88.com/topic/54439

1540 次点击

文章 [ 3 ] | 最新文章 5 年前

• 1 楼

Exosylver 5 年前

words =[]


def count_the_fruits():
    for fruit in fruits:
        if words.count(fruit) >=1:
            continue
        words.append((fruit, fruits.count(fruit)))
    print(words)


fruits = ["apple", "banana","grape", "kiwi", "banana", "apple", "apple", "watermelon", "kiwi", "banana", "apple"]
count_the_fruits()

• 2 楼

Daniel 5 年前

怎么样?

def count_the_fruits(fruits, fruits_to_check_for):

    # initialize variables:
    fruit_count = {}

    # iterate over each fruit in fruit list:
    for fruit in fruits_to_check_for:

        # count number of occurences:
        number_of_fruits = len([x for x in fruits if x==fruit])

        # add to dictionary:
        fruit_count[fruit] = number_of_fruits

    return fruit_count



if __name__ == '__main__':

    fruits = ['apple', 'banana', 'grape',       'kiwi', 
              'banana',  'apple', 'apple', 'watermelon', 
                'kiwi', 'banana', 'apple',]

    fruits_to_check_for = ['apple', 'banana']

    result = count_the_fruits(fruits, fruits_to_check_for)

    print(result)

• 3 楼

Sayandip Dutta 5 年前

它只给你一个计数是因为你只在寻找一个。试试这个:

fruits = ['apple', 'banana', 'grape', 'kiwi', 'banana', 'apple',
          'apple', 'watermelon', 'kiwi', 'banana', 'apple']
words = ["apple", "banana", "kiwi"]

def count_the_fruits(fruits, words):
    # This is a dict comprehension
    counts = {word: fruits.count(word) for word in words}
    return counts

print(count_the_fruits(fruits, words))

输出:

{'apple': 4, 'banana': 3, 'kiwi': 2}

登录后回复