R:根据属性将XML节点的子元素放入数据框中

import xml.etree.ElementTree as ET
import pandas as pd

# 解析XML文件
tree = ET.parse('example.xml')
root = tree.getroot()

# 定义数据框的列
columns = ['Attribute', 'Value']

# 创建空的数据框
df = pd.DataFrame(columns=columns)

# 遍历XML节点
for node in root.iter('Node'):
    # 提取子元素
    for child in node:
        # 获取子元素的属性和值
        attribute = child.attrib['attribute']
        value = child.text
        
        # 将属性和值添加到数据框中
        df = df.append(pd.Series([attribute, value], index=columns), ignore_index=True)

# 打印数据框
print(df)

<Root>
    <Node>
        <Child attribute="A">Value 1</Child>
        <Child attribute="B">Value 2</Child>
    </Node>
    <Node>
        <Child attribute="C">Value 3</Child>
        <Child attribute="D">Value 4</Child>
    </Node>
</Root>

  Attribute    Value
0         A  Value 1
1         B  Value 2
2         C  Value 3
3         D  Value 4