Python Pandas按固定词数拆分字符串列为多行且其余列保留实现

你的原有代码存在两个问题：

• apply作用于整个DataFrame的所有列，而非仅需要拆分的package_code列
• 没有将group_words返回的生成器转换为列表，导致最终输出为生成器对象而非拆分后的文本内容

你可以通过「对目标列单独生成分组列表 + explode拆分为多行」的方式实现需求，完整代码如下：

import pandas as pd

# 示例数据
df = pd.DataFrame({
    "order_id":[1,3,7],
    "order_date":["20/5/2018","22/5/2018","23/5/2018"], 
    "package":["p1","p4","p5,p6"],
    "package_code":["As he crossed toward the pharmacy at the","he was dancing in the","they were playing football"]
})

# 分组拆分函数
def group_words(s, n):
    words = s.split()
    for i in range(0, len(words), n):
        yield ' '.join(words[i:i+n])

# 第一步：将package_code列每个值转成分组后的列表
n = 5 # 每5个词一组
df['package_code'] = df['package_code'].apply(lambda x: list(group_words(x, n)))

# 第二步：将列表拆分为多行，其余列值自动复用原行内容
df = df.explode('package_code', ignore_index=True)

print(df)

运行结果 #

order_id order_date package              package_code
0         1  20/5/2018      p1   As he crossed toward the
1         1  20/5/2018      p1          pharmacy at the
2         3  22/5/2018      p4       he was dancing in the
3         7  23/5/2018   p5,p6  they were playing football

如果你的pandas版本低于0.25不支持explode，可使用如下兼容写法：

df = df.set_index(['order_id', 'order_date', 'package'])['package_code'].apply(pd.Series).stack().reset_index(drop=True, level=-1).reset_index(name='package_code')

内容的提问来源于stack exchange，提问作者user2543622