Поиск по xml-файлу

Question

Пишу программу по реализации алгоритмов по графам(поиск в ширину и т.д)

Писал функцию поиска соседних вершин, но выдает ошибку

Traceback (most recent call last):
    File "C:\Users\USER\Desktop\ia_algoritm\algoritm.py", line 60, in <module>
    a = neighbour(graph,p)
    File "C:\Users\USER\Desktop\ia_algoritm\algoritm.py", line 29, in neighbour
    edge = graph_[i].attrib
    KeyError: 0

def neighbour(filename,node):
    niegh = []
    tree = ET.parse(filename)
    root = tree.getroot()
    graph_ = root[2].attrib
    for i in range(0,47):
        edge = graph_[i].attrib
        source = edge.get('source')
        target = edge.get('target')
        if (source == node):
            niegh.append(target)
    return niegh
p = start(graph)
a = neighbour(graph,p)
print(a)

xml-файл

<?xml version="1.0" encoding="UTF-8"?>
<root>
   <algorithm type="dijkstra"/> 
   <task start.id="A" goal.id="L"/>
   <graph type="general">
    <edge source="A" target="B" weight="3"/>
    <edge source="B" target="A" weight="3"/>
    <edge source="A" target="C" weight="5"/>
    <edge source="C" target="A" weight="5"/>
    <edge source="A" target="D" weight="4"/>
    <edge source="D" target="A" weight="4"/>
    <edge source="B" target="E" weight="5"/>
    <edge source="E" target="B" weight="5"/>
    <edge source="C" target="F" weight="3"/>
    <edge source="F" target="C" weight="3"/>
    <edge source="D" target="F" weight="4"/>
    <edge source="F" target="D" weight="4"/>
    <edge source="D" target="E" weight="3"/>
    <edge source="E" target="D" weight="3"/>
    <edge source="D" target="G" weight="6"/>
    <edge source="G" target="D" weight="6"/>
    <edge source="E" target="G" weight="4"/>
    <edge source="G" target="E" weight="4"/>
    <edge source="E" target="J" weight="7"/>
    <edge source="J" target="E" weight="7"/>
    <edge source="F" target="G" weight="5"/>
    <edge source="G" target="F" weight="5"/>
    <edge source="F" target="H" weight="6"/>
    <edge source="H" target="F" weight="6"/>
    <edge source="G" target="H" weight="7"/>
    <edge source="H" target="G" weight="7"/>
    <edge source="G" target="J" weight="4"/>
    <edge source="J" target="G" weight="4"/>
    <edge source="H" target="I" weight="4"/>
    <edge source="I" target="H" weight="4"/>
    <edge source="I" target="K" weight="8"/>
    <edge source="K" target="I" weight="8"/>
    <edge source="I" target="L" weight="4"/>
    <edge source="L" target="I" weight="4"/>
    <edge source="J" target="K" weight="6"/>
    <edge source="K" target="J" weight="6"/>
    <edge source="J" target="N" weight="5"/>
    <edge source="N" target="J" weight="5"/>
    <edge source="K" target="L" weight="2"/>
    <edge source="L" target="K" weight="2"/>
    <edge source="K" target="M" weight="3"/>
    <edge source="M" target="K" weight="3"/>
    <edge source="K" target="N" weight="3"/>
    <edge source="N" target="K" weight="3"/>
    <edge source="L" target="M" weight="4"/>
    <edge source="M" target="L" weight="4"/>
    <edge source="M" target="N" weight="4"/>
    <edge source="N" target="M" weight="4"/>
</graph>

Answer 1

Не совсем понимаю, что вы хотите сделать, но я написал программу, которая ищет в вашем xml-файле указанный source и возвращает все подходящие target.

from re import findall

def search(fname, node):
    r = []
    with open(fname, "r", encoding = "utf-8") as f :
        for line in f :
            if line.startswith("\t\t") :
                parts = findall(r"\S+", line)[1 :]
                parts[-1] = parts[-1][: -2] if parts[-1].endswith("/>") else parts[-1][: -1]
                tags = dict()
                for part in parts :
                    splitted = part.split("=")
                    tags.update({splitted[0]: splitted[1][1 : -1]})
                if tags["source"] == node :
                    r += [tags["target"]]
        return r

fname = "file.xml"

print(search(fname, "E"))
# ['B', 'D', 'G', 'J']

Answer 2

Поле attrib -- возвращает атрибуты элемента, а root[2] это <graph type="general">:

graph_ = root[2].attrib
# {'type': 'general'}

Для перебора детей graph используйте итерацию по циклу.

Попробуйте:

from xml.etree import ElementTree as ET


def neighbour(filename, node):
    niegh = []
    tree = ET.parse(filename)
    root = tree.getroot()
    graph = root[2]

    for edge in graph:
        source = edge.get('source')
        target = edge.get('target')

        if source == node:
            niegh.append(target)

    return niegh

graph = 'graph.xml'
a = neighbour(graph, 'A')
print(a)
# ['B', 'C', 'D']

БЛОГ НА HUSL

Поиск по xml-файлу

Ответы (2 шт):