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copied!<p>Here is a more generic approach. Every node is classified as one of three cases:</p> <ul> <li>If the node name is of kind <code>rows</code>, then the data frames from child nodes will result in different rows of the result.</li> <li>If the node name is of kind <code>cols</code>, then the data frames from child nodes will result in different columns of the result.</li> <li>If the node name is of kind <code>value</code>, then a data frame with a single value will be constructed, using the node name as the column name and the node value as the column value.</li> <li>For all three cases, attributes of the node will be added to the data frame.</li> </ul> <p>The call for your application is given towards the bottom.</p> <pre class="lang-r prettyprint-override"><code>library(XML) zeroColSingleRow <- function() { res <- data.frame(dummy=NA) res$dummy <- NULL stopifnot(nrow(res) == 1, ncol(res) == 0) return (res) } xml2df <- function(node, classifier) { if (! inherits(node, c("XMLInternalElementNode", "XMLElementNode"))) { return (zeroColSingleRow()) } kind <- classifier(node) if (kind == "rows") { cdf <- lapply(xmlChildren(node), xml2df, classifier) if (length(cdf) == 0) { res <- zeroColSingleRow() } else { names <- unique(unlist(lapply(cdf, colnames))) cdf <- lapply(cdf, function(i) { missing <- setdiff(names, colnames(i)) if (length(missing) > 0) { i[missing] <- NA } return (i) }) res <- do.call(rbind, cdf) } } else if (kind == "cols") { cdf <- lapply(xmlChildren(node), xml2df, classifier) if (length(cdf) == 0) { res <- zeroColSingleRow() } else { res <- cdf[[1]] if (length(cdf) > 1) { for (i in 2:length(cdf)) { res <- merge(res, cdf[[i]], by=NULL) } } } } else { stopifnot(kind == "value") res <- data.frame(xmlValue(node)) names(res) <- xmlName(node) } if (ncol(res) == 0) { res <- zeroColSingleRow() } attr <- xmlAttrs(node) if (length(attr) > 0) { attr <- do.call(data.frame, as.list(attr)) res <- merge(attr, res, by=NULL) } rownames(res) <- NULL return(res) } doc<-xmlParse("test.xml") xml2df(xmlRoot(doc), function(node) { name <- xmlName(node) if (name %in% c("watchers", "results")) return("rows") # make sure to treat results/result different from watcher/result if (name %in% c("watcher", "result") && xmlName(xmlParent(node)) == paste0(name, "s")) return("cols") return("value") }) </code></pre>

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