Python Pandas - 合并具有多对一关系的 DataFrame
要合并PandasDataFrame，请使用该merge()函数。在许多对一的关系是通过在“设置上都DataFrames实施验证了”参数merge()的功能，即-
validate = “many-to-one” or validate = “m:1”
多对一关系检查合并键在正确的数据集中是否唯一。
首先，让我们创建我们的第一个DataFrame-
dataFrame1 = pd.DataFrame(
{
"Car": ['BMW', 'Audi', 'Mustang', 'Bentley', 'Jaguar'],"Units": [100, 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-
#
#以多对一的关系合并PandasDataFrame
#
import pandas as pd
#创建DataFrame1
dataFrame1 = pd.DataFrame(
{
"Car": ['BMW', 'Audi', 'Mustang', 'Bentley', 'Jaguar'],"Units": [100, 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 "many-to-one" in "validate" parameter
mergedRes = pd.merge(dataFrame1, dataFrame2, validate ="many_to_one")
print("\nMerged dataframe with many-to-one relation...\n", mergedRes)输出结果这将产生以下输出-
DataFrame1 ...
Car Units
0 BMW 100
1 Audi 110
2 Mustang 80
3 Bentley 110
4 Jaguar 90
DataFrame1 ...
Car Reg_Price
0 BMW 7000
1 Lexus 1500
2 Tesla 5000
3 Mustang 8000
4 Mercedes 9000
5 Jaguar 6000
Merged dataframe with many-to-one relation...
Car Units Reg_Price
0 BMW 100 7000
1 Mustang 80 8000
2 Jaguar 90 6000