尝试在R中使用read_xml函数并获取0的列表时出现问题？

我处理的这个.xml文件看起来有点凌乱。我试图得到一个由四列组成的四列数据帧，名为“x1”、“y1”、“x2”、“y2”。很抱歉，我无法附加xml文档，但这里是文本

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这里有一个解决方案，将所有的X&Y值分成两半，并重新组合到最终的数据帧中

#find all of the attributes values (list of x & y values)
values <-file  %>% xml_find_all(".//Vertices") %>% xml_find_all(".//V") %>% xml_attrs() 

#bind into a data frame and alternate naming rows
values <-bind_rows(values) %>%
   mutate_all(as.integer)

rownumbers <- rep(c(1,2), (nrow(values)/2))

#split by the odd and even rows and bind into final answer
#make unique column names
answer <- cbind(values[rownumbers==1,], values[rownumbers==2,])  
names(answer) <- make.names(names(answer), unique = TRUE)

#查找所有属性值（x&y值列表）
值%xml\u find\u all（“.//顶点”）%%>%xml\u find\u all（“.//V”）%%>%xml\u attrs（）
#绑定到数据框和备用命名行中
价值%
mutate_all（作为.integer）
行数您好，在提问之前，最好先制作一个类似您的data.frame的示例。使问题更容易理解。能否检查xml文件的格式是否正确？至少在您共享的示例中，
（带s的）没有关闭，因此我必须添加关闭并删除末端的部分，这看起来像是复制错误。
#find all of the attributes values (list of x & y values)
values <-file  %>% xml_find_all(".//Vertices") %>% xml_find_all(".//V") %>% xml_attrs() 

#bind into a data frame and alternate naming rows
values <-bind_rows(values) %>%
   mutate_all(as.integer)

rownumbers <- rep(c(1,2), (nrow(values)/2))

#split by the odd and even rows and bind into final answer
#make unique column names
answer <- cbind(values[rownumbers==1,], values[rownumbers==2,])  
names(answer) <- make.names(names(answer), unique = TRUE)