Reply To: Execution

Ivan,

If you folks haven’t defined rdivu, may I please have permission to suggest (namely speculate publicly) on what rdivu might calculate? Or would you prefer I email that to you first, for your approval.

I really doubt that the rudiments of numerical analysis, Taylor series and the Newton-Raphson algorithm{1} would have anything patentable, but I’d like to help — and thus try my best not to cause Millcomputing any IP headaches.

Unless I’m mis-remembering, the convergence of any Newton-Raphson-like algorithm will depend strongly on the accuracy of what rdivu produces. So there’ll probably be a trade-off between the hardware/speed cost of implementing rdivu and the precision — and thus how many iterations are needed to converge (for a given width of input args.)

Is there an existing forum category you’d like to see this under?
Actually, my instinct is to put it on the Wiki (once I have something coherent), under community-contributed software. That way we have history and multiple people can try their hand at emulating division.

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{1} According to a lecture I heard some years ago at NIST (wish I could recall the speaker’s name), Newton’s original approximation method, in his Principia Mathematica is rather different from the modern Newton-Raphson root-finding algorithm. (But Raphson still got second billing. So it goes….)