如何在Python中统计列表条目包含另一列表单词的数量

我有两个列表：

• List1的每个条目是一段文本，示例：

List1 = ["My house is red", "The dog is black", "The table is small", "The wind is cold"]

• List2的每个条目是单个单词，示例：

List2 = ["house", "red", "wind", "small", "big", "dog", "cat", "fox", "car"]

需要统计List1中每个文本条目包含多少个List2里的单词，期望得到结果列表：

[2, 1, 1, 1]

尝试过List1.count(List2)，但该方法仅接受单个值；也写了for循环但逻辑存在问题：

List 3 = []

for w in List2:
    if w in List1:
      List3 = 1
    else:
      List3 = List3[w] + 1

寻求正确的实现方案。

方法1：基础嵌套循环 #

遍历List1的每个句子，拆分句子为单词后，逐个检查是否在List2中，统计符合条件的数量：

List1 = ["My house is red", "The dog is black", "The table is small", "The wind is cold"]
List2 = ["house", "red", "wind", "small", "big", "dog", "cat", "fox", "car"]

List3 = []
for sentence in List1:
    # 按空格拆分句子为单词（若句子含标点，可先做清洗，比如用strip()去除标点）
    words = sentence.split()
    match_count = 0
    for word in words:
        if word in List2:
            match_count += 1
    List3.append(match_count)

print(List3)  # 输出: [2, 1, 1, 1]

方法2：高效集合查询（推荐） #

把List2转为集合，集合的成员查询效率远高于列表（O(1) vs O(n)），适合List2元素较多的场景，再结合生成器表达式简化代码：

List1 = ["My house is red", "The dog is black", "The table is small", "The wind is cold"]
# 转List2为集合
List2_set = {"house", "red", "wind", "small", "big", "dog", "cat", "fox", "car"}

List3 = []
for sentence in List1:
    words = sentence.split()
    # 用生成器统计符合条件的单词数
    match_count = sum(1 for word in words if word in List2_set)
    List3.append(match_count)

print(List3)  # 输出: [2, 1, 1, 1]

方法3：列表推导式（极简写法） #

将上述逻辑压缩为一行列表推导式，更简洁：

List1 = ["My house is red", "The dog is black", "The table is small", "The wind is cold"]
List2_set = {"house", "red", "wind", "small", "big", "dog", "cat", "fox", "car"}

List3 = [sum(1 for word in sentence.split() if word in List2_set) for sentence in List1]
print(List3)  # 输出: [2, 1, 1, 1]

原代码问题说明 #

你之前的循环逻辑存在多处错误：

1. 遍历对象错误：应该遍历List1的句子，而非List2的单词
2. 列表操作错误：List3被错误赋值为整数，正确做法是用append()向列表添加元素
3. 索引错误：List3[w]试图用单词作为列表索引，这不符合列表的索引规则（列表只能用整数索引）

内容的提问来源于stack exchange，提问作者Ruslan