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compile - Compilation of Total with compensated summation


I sometimes obtain an unexpected error when trying to call a compiled version of Total with compensated summation turned on. More specifically I define


f1 = Compile[{{x,_Real,1}},Total[x],CompilationTarget->"C"];
f2 = Compile[{{x,_Real,1}},Total[x,Method->"CompensatedSummation"],CompilationTarget->"C"];

When I call the functions via


x=RandomReal[{0,1},10^5]
f1[x]

f2[x]

I sometimes, but not always, obtain a CompiledFunction::cfte error, informing me that the



"Compiled expression [some large number of order $10^{5}$] should be a rank 1 tensor of machine-size real numbers."



I have studied the documentation of that error but have been unable to isolate the problem any further. The results of f1 and f2 differ by up to $1\times 10^{-9}$ and the difference becomes even larger for larger input vectors, so I'd quite like to be able to use the (presumably more accurate) version with compensated summation turned on.


Question: What causes the CompiledFunction::cfte error and how can I avoid it when compiling Total with compensated summation?


In case it matters I am using version 9.0 for Linux x86 (64-bit).




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