MathGroup Archive 2013

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Russian Peasant Multiplication / was question on how to do this

On Saturday, June 29, 2013 2:47:03 AM UTC-6, Richard Fateman wrote:
> Dave --
> 1.  You should try to come up with a useful subject line
> in the future.
> 2. It is called Russian Peasant Multiplication (which you may
> find on Google).
> 3. There is no reason to believe that a procedural algorithm
> has a formula, but in this case I think the inverse is known
> as division :)

I am sorry for posting a question that is improper.  It is a matter of rounding as a floor or ceiling question I guess wondering nomenclature.  If the lowest count on the numbers in a multiply are let's say 7 and 5.  We multiple these and get 35.  How does on drop the 5 into the lowest of the answer and carry the 3?  Since 7 and 5 and also 35 are know known we do this..  In base ten we multiply by ten.  Divide out the seven and get fifty.  Divide that by ten and get the 5 drop out number.  Then put the the thirty five minus the drop out number and then divide by ten again.  Gives three.  The carry number.  So I guess in using this for any base number system we do have a divide as an inverse function for any variables in the course of a multiply.

  • Prev by Date: Complex path integral wrong
  • Next by Date: Finding a function within an arbitrary expression
  • Previous by thread: Russian Peasant Multiplication / was question on how to do this
  • Next by thread: Create Modelica Models within Mathematica