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xmlrmarkup

How to handle two step conversion in XML using R?

I am parsing one xml using R (XML package). XML has following markup. 

 <  &lt;
 >  &gt;
 &  &amp;

Input Text: 
       My age is &amp;gt; 65 years years. 

       output: My age is gt;65 years.

Expected output: My age is >65 years. 

  How to get 2-step(1) for converting &amp; into & (2)  &gt; into '>' ?
Solution

  • You could write a function like this

    batchgsub <- function(patternmatrix, string) {
    for (i in 1:nrow(patternmatrix)) {
        p = patternmatrix[i,1]
        r = patternmatrix[i,2]
        string <- gsub(p,r,string)
    }
    return(string)
}

    and specify your patterns to be replaced like this

    > pm
     [,1]    [,2]
[1,] "&amp;" "&" 
[2,] "&gt;"  ">"

    Then you can "chain" the replacements as many times as you want. 

    > s <- "My age is &amp;gt; 65 years."
> batchgsub(pm, s)
[1] "My age is > 65 years."