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This Guy Just Found a Faster Way to Multiply
www.popularmechanics.com ^ | By David Grossman Oct 18, 2019

Posted on 10/21/2019 2:51:31 PM PDT by Red Badger

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To: Red Badger

Faster than I can punch the numbers into a calculator?


21 posted on 10/21/2019 3:43:20 PM PDT by Tallguy (Facts be d@mned! The narrative must be protected at all costs!)
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To: Songcraft
Augustus the Strong, Elector of Saxony, later King of Poland and Grand Duke of Lithuania (1670-1733), supposedly had 365 illegitimate children (and one legitimate child, a son).

So he knew how to multiply. How fast, I don't know. If spread out evenly over his adult life that would be only about 9 kids a year.

22 posted on 10/21/2019 3:50:02 PM PDT by Verginius Rufus
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To: Tallguy

“Faster than I can punch the numbers into a calculator?”

You didn’t read the article!


23 posted on 10/21/2019 3:53:32 PM PDT by TexasGator (Z1z)
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To: Red Badger

This same method came to me in 10th grade in 1972, in an epiphany. I showed my teacher, but we were entering the period of calculators so it was useless.


24 posted on 10/21/2019 3:56:24 PM PDT by tired&retired (Blessings)
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To: Red Badger

Is it faster than The Trachtenberg Speed of speed math? Remember all those ads in magazines back in the 1960s?


25 posted on 10/21/2019 4:26:12 PM PDT by Ruy Dias de Bivar
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Schönhage–Strassen algorithm

https://en.wikipedia.org/wiki/Sch%C3%B6nhage%E2%80%93Strassen_algorithm


26 posted on 10/21/2019 4:59:30 PM PDT by lurked_for_a_decade (Imagination is more important than knowledge! ( e_uid == 0 ) != ( e_uid = 0 ). I Read kernel code.)
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To: lurked_for_a_decade

It’s not a very clear explanation.
I figured it out though.


27 posted on 10/21/2019 5:31:04 PM PDT by scrabblehack
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To: Red Badger

The fastest multiplication is done by illegals.


28 posted on 10/21/2019 5:36:32 PM PDT by Joe Bfstplk (No real problem has a solution.)
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To: Red Badger

Too bad he doesn’t demonstrate it. We’d all like to see how fast it works.


29 posted on 10/21/2019 5:50:31 PM PDT by GOP_Party_Animal
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To: Verginius Rufus

How did that legitimate one slip through the cracks there?

Augustus the Strong must have had trouble doing the math when trying to keep track of all those offspring.   He could have done that math a bit faster if he had just had more fingers and toes to work with...


       
       

30 posted on 10/21/2019 6:08:44 PM PDT by Songcraft
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To: steve86
Software engineer here.

The way I just solved the problem in my head was like this: 1) 314 X 1.5 (one and a half of 314) and I get 450 + 21 which is 471. But since it's 150 instead of 1.5, make that 47,100.

2) 314 X 9 = 314 X 3 X 3 = 942 X 3 = 2826.

3) 47,100 + 2826 = 49,926. Each one of those steps is fairly easy to do in your head -- a heck of lot easier than figuring out logarithms.

31 posted on 10/21/2019 6:17:02 PM PDT by Tell It Right (1st Thessalonians 5:21 -- Put everything to the test, hold fast to that which is true.)
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To: Red Badger

Except computers don’t multiply digit by digit.


32 posted on 10/21/2019 6:19:03 PM PDT by CodeToad (Arm Up! They Are!)
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To: TexasGator

I need an algorithm to help me read faster.


33 posted on 10/21/2019 6:27:18 PM PDT by MPJackal ("From my cold dead hands.")
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To: Republic_Venom

I don’t usually monkey around with Riemann zeta functions but...I do remember about Ramanujan and the taxicab number!

A much better explanation and fun too!
https://plus.maths.org/content/infinity-or-just-112

The trick
So how did the people in the Numberphile video “prove” that the natural numbers all add up to -1/12? The real answer is that they didn’t. Watching the video is like watching a magician and trying to spot them slipping the rabbit into the hat.


34 posted on 10/21/2019 7:06:27 PM PDT by DUMBGRUNT
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To: Songcraft

Hallmark loved him...366 kids, that’s a birthday card a day to buy.


35 posted on 10/21/2019 7:27:47 PM PDT by Verginius Rufus
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To: Red Badger

Back in the day you used your slide rule to do calcutions or resorted to tables of logarithms. Multiplication is accomplished by adding the logarithms of the numbers then looking up the antilog of the sum in another set of tables. I still have my old slide rule and also kept a well worn book of logs. My grandkids will someday be amused. Intetesting the Saturn V moon rocket was designed with this technology.


36 posted on 10/21/2019 8:18:32 PM PDT by The Great RJ ("Socialists are happy until they run out of other people's money." Margaret Thatcher)
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