Hello,
 
I am trying to implement function for reading/writing some XML file format.
One feature of that XML format is that a lot of binary data is stored in
Base64 format, and since R's XML package does not seem to support it, I just
wrote my own converter from "raw" format to Base64, and back. However one
place I have problems with is conversion from vector of doubles to vector of
"raw"s. 

I was expecting equivalent of C casting operation, like:
	    double *doubleVec;
	    unsigned char* rawVec;
	    rawVec = (unsigned char*) doubleVec;
Or if compiler complains:
	    rawVec = (unsigned char*) ((void*) doubleVec);

Unfortunately I can not find equivalent function in R. Simple minded:
	    doubleVec = (1:4)*pi
	    rawVec = as.raw(doubleVec)
	    as.double(rawVec)
Does not seem to work (output: 3  6  9 12, instead of: 3.141593  6.283185
9.424778 12.566371) .

The only way I figured out how to do it is by using:
	 raw2double = function(x)
	 {
	   writeBin(as.raw(x), "temp.bin")
	   return( readBin("temp.bin", "double", n=length(x)%/%8) )
	 }

	 double2raw = function(x)
	 {
	   writeBin(as.double(x), "temp.bin")
	   return( readBin("temp.bin", "raw", n=length(x)*8) )
	 }
Than:
	  rawVec = double2raw(doubleVec)
	  raw2double(rawVec)
Gives correct results. 

Is there any other way that does not use temporary files to do this simple
casting, that does not involve writing my own C code (which I am trying to
avoid).


Jarek
=====================================\====                 
 Jarek Tuszynski, PhD.                               o / \ 
 Science Applications International Corporation  <\__,|  
 (703) 676-4192                        ">  \
 Jaroslaw.W.Tuszynski@saic.com                   `    \



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