Python Pandas – 使用一对多关系合并 DataFrame
要合并PandasDataFrame，请使用该merge()函数。在一个一对多的关系是通过在“设置上都DataFrames实施验证了”参数merge()的功能，即-
validate = “one-to-many” or validate = “1:m”
一对多关系检查合并键在左侧数据集中是否唯一。
首先，让我们创建我们的第一个DataFrame-
dataFrame1 = pd.DataFrame(
{
"Car": ['BMW', 'Lexus', 'Audi', 'Mustang', 'Bentley', 'Jaguar'],"Units": [100, 150, 110, 80, 110, 90]
}
)现在，让我们创建我们的第二个DataFrame-
dataFrame2 = pd.DataFrame(
{
"Car": ['BMW', 'Lexus', 'Tesla', 'Mustang', 'Mercedes', 'Jaguar'],"Reg_Price": [7000, 1500, 5000, 8000, 9000, 6000]
}
)示例
以下是代码-
import pandas as pd
#创建DataFrame1
dataFrame1 = pd.DataFrame(
{
"Car": ['BMW', 'Lexus', 'Audi', 'Mustang', 'Bentley', 'Jaguar'],"Units": [100, 150, 110, 80, 110, 90]
}
)
print("DataFrame1 ...\n",dataFrame1)
#创建DataFrame2
dataFrame2 = pd.DataFrame(
{
"Car": ['BMW', 'Lexus', 'Tesla', 'Mustang', 'Mercedes', 'Jaguar'],"Reg_Price": [7000, 1500, 5000, 8000, 9000, 6000]
}
)
print("\nDataFrame2 ...\n",dataFrame2)
# merge DataFrames with "one-to-many" in "validate" parameter
mergedRes = pd.merge(dataFrame1, dataFrame2, validate ="one_to_many")
print("\nMerged dataframe with one-to-many relation...\n", mergedRes)输出结果这将产生以下输出-
DataFrame1 ...
Car Units
0 BMW 100
1 Lexus 150
2 Audi 110
3 Mustang 80
4 Bentley 110
5 Jaguar 90
DataFrame2 ...
Car Reg_Price
0 BMW 7000
1 Lexus 1500
2 Tesla 5000
3 Mustang 8000
4 Mercedes 9000
5 Jaguar 6000
Merged dataframe with one-to-many realtion ...
Car Units Reg_Price
0 BMW 100 7000
1 Lexus 150 1500
2 Mustang 80 8000
3 Jaguar 90 6000