'working directory error when read multiple xml files in R and combine the data

I am trying to parse/read the multiple xml files from my current data and try to combine them together.

current type of XMLResponse is character

And my sample xml file is like this:

<ApplicationResponse>
    <Service Name="AlternativeCreditAttributes">
      <Categories>
        <Category Name="Default">
          <Attributes>
            <Attribute Name="ACA_ACH_NSF_12M" Value="0" />
            <Attribute Name="ACA_ACH_NSF_18M" Value="0" />
            <Attribute Name="ACA_ACH_NSF_24M" Value="0" />
            <Attribute Name="ACA_ACH_NSF_3M" Value="0" />
            <Attribute Name="ACA_ACH_NSF_6M" Value="0" />
            <Attribute Name="ACA_ACH_NSF_9M" Value="0" />
            <Attribute Name="ACA_ACH_NSF_AMT_12M" Value="" />
            <Attribute Name="ACA_ACH_NSF_AMT_18M" Value="" />
            <Attribute Name="ACA_ACH_NSF_AMT_24M" Value="" />
            <Attribute Name="ACA_ACH_NSF_AMT_3M" Value="" />
            <Attribute Name="ACA_ACH_NSF_AMT_6M" Value="" />
            <Attribute Name="ACA_ACH_NSF_AMT_9M" Value="" />
            <Attribute Name="ACA_ACH_NSF_AMT_EVER" Value="600" />
            <Attribute Name="ACA_ACH_NSF_EVER" Value="2" />
            <Attribute Name="ACA_ACH_NSF_MONTHS_SINCE_NEWEST" Value="41" />
            <Attribute Name="ACA_ACH_NSF_MONTHS_SINCE_OLDEST" Value="41" />
          </Attributes>
        </Category>
      </Categories>
    </Service>
</ApplicationResponse>

I have successfully pulled one single file based on the following code:

doc<-read_xml(Data$XMLResponse[1])
  # setNames(data.frame(
    cols<- xml_attr(xml_find_all(doc, "//Attribute"), "Name")
    rows<- xml_attr(xml_find_all(doc, "//Attribute"), "Value")
  # ),
out  <- data.frame(rows, row.names = cols)
out

But when I tried to use lapply to pull multiple files base on this answer, I met the Error on working directory.

Error: 'NA' does not exist in current working directory

Below is the code I use. Please let me know if you know the issue or if you need any details on this problem. Thanks in advance. 

df_list <- lapply(Data$XMLResponse, function(f) {
  doc <- read_xml(f)
  setNames(data.frame(
    xml_attr(xml_find_all(doc, "//Attribute"), "Name"),
    xml_attr(xml_find_all(doc, "//Attribute"), "Value")
  ),c("Name", f))
})
rxmllapplyworking-directory


Solution 1:[1]

Here is an approach that uses a for() loop to collect all of the values from each xml file that you have stored within Data$XMLResponse. Code assumes every xml file has exactly the same length of "Attributes" in the same order.

library(xml2)    
#create a blank list
datalist = list()
#loop through your column of xml responses to extract the values you want.
for(i in 1:length(Data$XMLResponse)){
temp_vals<-read_xml(Data$XMLResponse[i])
temp_vals<-xml_attr(xml_find_all(temp_vals, "//Attribute"), "Value")
#assign these values to your data list
datalist[[i]]<-temp_vals
}

#bind the data from the xml files together
your_data = do.call(rbind, datalist)

Then get column names:

your_column_names<-xml_attr(xml_find_all(Data$XMLResponse[1], "//Attribute"), "Name")
doc<-setNames(data.frame(matrix(ncol = length(your_column_names), nrow = 0)), your_column_names)

And then use rbind() to bind your data with your column names 

rbind(doc,your_data)

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1

Related Questions