要选择XML_PARSE_HUGE"，需要在选项中进行规定.XML:::parserOptions 列出选项选项:

To choose "XML_PARSE_HUGE" you need to stipulate it in the options. XML:::parserOptions lists the option choices:

> XML:::parserOptions
   RECOVER      NOENT    DTDLOAD    DTDATTR   DTDVALID    NOERROR  NOWARNING 
         1          2          4          8         16         32         64 
  PEDANTIC   NOBLANKS       SAX1   XINCLUDE      NONET     NODICT    NSCLEAN 
       128        256        512       1024       2048       4096       8192 
   NOCDATA NOXINCNODE    COMPACT      OLD10  NOBASEFIX       HUGE     OLDSAX 
     16384      32768      65536     131072     262144     524288    1048576 

例如

> HUGE
[1] 524288

使用这些选项中的任何一个声明整数向量就足够了.你的情况

It is suffiecient to declare a vector of integers with any of these options. In your case

xmlTreeParse(i, useInternalNodes = TRUE, options = HUGE)