在pandas中将多行追加到单行中

import pandas as pd

# 创建一个示例DataFrame
data = {
    'id': [1, 1, 2, 2, 3],
    'value1': ['a', 'b', 'c', 'd', 'e'],
    'value2': [10, 20, 30, 40, 50]
}
df = pd.DataFrame(data)

# 使用groupby和agg将多行合并为一行
result = df.groupby('id').agg({'value1': ''.join, 'value2': list}).reset_index()

print(result)

   id value1     value2
0   1      ab  [10, 20]
1   2      cd  [30, 40]
2   3      e       [50]

import pandas as pd

# 创建一个示例DataFrame
data = {
    'id': [1, 1, 2, 2, 3],
    'value1': ['a', 'b', 'c', 'd', 'e'],
    'value2': [10, 20, 30, 40, 50]
}
df = pd.DataFrame(data)

# 使用apply自定义合并逻辑
def merge_rows(group):
    merged_row = {
        'id': group['id'].iloc[0],
        'value1': ''.join(group['value1']),
        'value2': group['value2'].tolist()
    }
    return pd.Series(merged_row)

result = df.groupby('id').apply(merge_rows).reset_index(drop=True)

print(result)

   id value1     value2
0   1      ab  [10, 20]
1   2      cd  [30, 40]
2   3      e       [50]