Example for parsing XML file?
Hi Brigid.
Here are a few commands that should do what you want:
bri = xmlParse("myDataFile.xml")
tmp = t(xmlSApply(xmlRoot(bri), xmlAttrs))[, -1]
dd = as.data.frame(tmp, stringsAsFactors = FALSE,
row.names = 1:nrow(tmp))
And then you can convert the columns to whatever types you want
using regular R commands.
The basic idea is that for each of the child nodes of C,
i.e. the <T>'s, we want the character vector of attributes
which we can get with xmlAttrs().
Then we stack them together into a matrix, drop the "N"
and then convert the result to a data frame, avoiding
duplicate row names which are all "T".
(BTW, make certain the '-' on the second line is not in the XML content.
I assume that came from bringing the text into mail.)
HTH
D.
Brigid Mooney wrote:
Hi, I am trying to parse XML files and read them into R as a data frame, but have been unable to find examples which I could apply successfully. I'm afraid I don't know much about XML, which makes this all the more difficult. If someone could point me in the right direction to a resource (preferably with an example or two), it would be greatly appreciated. Here is a snippet from one of the XML files that I am looking to read, and I am aiming to be able to get it into a data frame with columns N, T, A, B, C as in the 2nd level of the heirarchy. <?xml version="1.0" encoding="utf-8" ?> - <C S="UnitA" D="1/3/2007" C="24745" F="24648"> <T N="1" T="9:30:13 AM" A="30.05" B="29.85" C="30.05" /> <T N="2" T="9:31:05 AM" A="29.89" B="29.78" C="30.05" /> <T N="3" T="9:31:05 AM" A="29.9" B="29.86" C="29.87" /> <T N="4" T="9:31:05 AM" A="29.86" B="29.86" C="29.87" /> <T N="5" T="9:31:05 AM" A="29.89" B="29.86" C="29.87" /> <T N="6" T="9:31:06 AM" A="29.89" B="29.85" C="29.86" /> <T N="7" T="9:31:06 AM" A="29.89" B="29.85" C="29.86" /> <T N="8" T="9:31:06 AM" A="29.89" B="29.85" C="29.86" /> </C> Thanks for any help or direction anyone can provide. As a point of reference, I am using R 2.8.1 and have loaded the XML package.
______________________________________________ R-help at r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.