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Happy Pi day!


aviatoreb

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8 minutes ago, Hyett6420 said:

Sorry why is it pi day?  Its the 14/3/2019, if i recall correctly pi is 3.1415926... so even if we use YOUR (yes only in the usa do you do this) date method then it cant be pi day because its 3142019 which is not pi.  I would have expected better from a maths scholar @aviatoreb ;)  

Drop the year and you've got his new N number. Also, over here it's singular:  math, formed by cutting the word "mathematics" at the fjrst syllable break.   

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6 hours ago, aviatoreb said:

You know what really bothers me?  Its my electrical engineering friends.  They think i should represent current since for some reason current is more important to them than imaginary numbers.  So since i is already used up they use j for the sqrt of negative one. ??!!

And as many on here know, but I will repeat because it is beautiful... 

Euler: exp(I theta)=cos(theta)+isin(theta) so exp(iPi)+1=0. (but those silly EE sorts say exp(jPi)+1=0)

I switched from EE to ME after an antenna design course that was full of imaginary number calculations.  I had enough trouble with real numbers.

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We had to do a fair bit of imaginary number calculations in IE.  They were pretty simple really, just keep the imaginary numbers with the imaginary numbers and the real numbers with the real numbers and you won't have any problems.  It's just like with friends... if you let your imaginary friends mingle with your real friends, that's when you start getting into trouble. :ph34r:

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1 hour ago, whiskytango said:

I switched from EE to ME after an antenna design course that was full of imaginary number calculations.  I had enough trouble with real numbers.

Some of my best friends are ME's.

Heck one of my sons is majoring in ME! ME's are good people.

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1 hour ago, skydvrboy said:

We had to do a fair bit of imaginary number calculations in IE.  They were pretty simple really, just keep the imaginary numbers with the imaginary numbers and the real numbers with the real numbers and you won't have any problems.  It's just like with friends... if you let your imaginary friends mingle with your real friends, that's when you start getting into trouble. :ph34r:

Same with Quaternions.

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2 hours ago, Hyett6420 said:

Sorry why is it pi day?  Its the 14/3/2019, if i recall correctly pi is 3.1415926... so even if we use YOUR (yes only in the usa do you do this) date method then it cant be pi day because its 3142019 which is not pi.  I would have expected better from a maths scholar @aviatoreb ;)  

Oh Andrew.  You aren't trying to corner me and my mathematical wit are you? (A circle has no corners).

1) Well it is conventional to speak in terms traditions of the country of residence.  So it is officially Pi day on 3/14 in the USA, every year.  The day of celebrating Pi.  Whether or not numerically accurate.  And all day it is Pi day.  Every year.  Further, I could only fit 3 digits per regulations of the FAA.  However, there is a tiny dot on my paint job between the 3 and the 14 and if you look close that dot is actually the true greek symbol used for Pi - my attempt to better honor the number.

2) In "the rest of the world" there is never a Pi day because there is never a 14th month.  Too bad for the world.

3) If we are worried the year. 2019, then who said I am necessarily using the date relative to the birth of Christ?  Maybe I dated relative to....

4) Now Pi is defined as the ratio of the length of the diameter of a PERFECT circle to its diameter.  No where does it say, "in base 10" but that we use base 10 is an accident of biology - of evolution that we humans have ten digits on our hands.  In base 8 for example, Pi is:

Octal base = 8,
3.11037 55242 10264 30215 14230 63050 56006 70163 21122 01116 02105 14763 07200 20273 72461 66116 33104 50512 02074 61615

http://turner.faculty.swau.edu/mathematics/materialslibrary/pi/pibases.html

and who has 8 digits?  Well Disney people of course!  Just ask Mickey Mouse (as drawn by Walt) how many digits he has.  OTOH in some "circles" people speak in base 20 in years past.  Just ask Abe, "Four score and 7 years ago today" (87 years).

 

   
 
Edited by aviatoreb
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@aviatoreb, nice discussion of base 10 vs. base 8. But much of our early math, as well as timekeeping up through today, was developed by the Sumerians and Babylonians  using base 12. Where did base 12 come from? They sure didn't have 12 fingers, and they wrote with flared sticks in small clay tablets later dried in the sun.

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7 minutes ago, Hank said:

@aviatoreb, nice discussion of base 10 vs. base 8. But much of our early math, as well as timekeeping up through today, was developed by the Sumerians and Babylonians  using base 12. Where did base 12 come from? They sure didn't have 12 fingers, and they wrote with flared sticks in small clay tablets later dried in the sun.

That's a good question which I don't know the answer.  We see vestige of other bases in our numbers system.  12: we speak of a dozen still.  And a foot has 12 inches.

And we speak of a score - base 20.

The 10 is clearly based on counting fingers and toes (so it seems). 8 I just posted for fun and contrasted to Disney characters which Walt drew with 8 digits to save time in the era of hand drawn cartoons.

The base 12 thing, I don't know the historical roots. I will poke around and get back to you!

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14 minutes ago, m20kmooney said:

Each human hand in fact has 12 phalanges (finger bones.) 3 in each of the four fingers. So it is possible to count to 12!

Yep, a quick search told me that my memory was wrong--Sumer used Base 60, from the 12 leftnand phalanges and the 5 righthand fingers. It makes for complicated math . . . .

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9 minutes ago, Hank said:

Yep, a quick search told me that my memory was wrong--Sumer used Base 60, from the 12 leftnand phalanges and the 5 righthand fingers. It makes for complicated math . . . .

Yikes!

9 minutes ago, Hank said:

Yep, a quick search told me that my memory was wrong--Sumer used Base 60, from the 12 leftnand phalanges and the 5 righthand fingers. It makes for complicated math . . . .

And the two flanges for thumbs. 14 per hand?

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The human thumb is a digit but not considered a finger. It is “opposable” meaning it faces and can touch the four fingers. This is true of most primates but humans have the most opposable thumbs. We can move our thumb farther across our hand than any other primate. Therefore we can use our thumb to point to and count the 12 phalanges of the fingers! 

Edited by m20kmooney
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1 minute ago, m20kmooney said:

The human thumb is not considered a finger. It is “opposable” meaning we can touch the four fingers with our thumb. Therefore we can use our thumb to point to and count the 12 phalanges of the fingers! 

You are speaking biology.

ask any 5 year old to count on their fingers and watch what happens.  I wonder if 5 year old child knows the anatomical definitions.

And I wonder how prehistoric man counted.  I wonder if prehistoric man knew the anatonomical definition.

i can barely spell anatonomical with an assist from autocorrect.

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Prehistoric man knew how to use the thumb as a pointer to touch the 12 phalanges of the fingers and count them. Also he knew he could grasp food and eat with one hand. All that thanks to the opposable thumb! Same goes for a 5 year old!

Edited by m20kmooney
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2 hours ago, m20kmooney said:

Prehistoric man knew how to use the thumb as a pointer to touch the 12 phalanges of the fingers and count them. Also he knew he could grasp food and eat with one hand. All that thanks to the opposable thumb! Same goes for a 5 year old!

I swear I have never carried on a critical discussion regarding phalanges before today.  Ever.

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If you want to be really advanced, count on your fingers in binary.  You can count to 1023 before you run out of fingers!  

Which reminds me of my favorite math joke.  There are only 10 kinds of people in this world... those who understand binary and those who don't.

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26 minutes ago, skydvrboy said:

If you want to be really advanced, count on your fingers in binary.  You can count to 1023 before you run out of fingers!  

Which reminds me of my favorite math joke.  There are only 10 kinds of people in this world... those who understand binary and those who don't.

Which reminds me of my favorite sociology joke:  I only hate two kinds of people.  Those who are intolerant of other cultures- and the Dutch.

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24 minutes ago, skydvrboy said:

Which reminds me of my favorite math joke.  There are only 10 kinds of people in this world... those who understand binary and those who don't.

I always heard that there are three kinds of people:  those who can count, and those who can't. 

1 hour ago, aviatoreb said:

I swear I have never carried in a critical discussion regarding phalanges before today.  Ever.

Yeah, me too. Or me neither. Same difference, right? 

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26 minutes ago, skydvrboy said:

If you want to be really advanced, count on your fingers in binary.  You can count to 1023 before you run out of fingers!  

Which reminds me of my favorite math joke.  There are only 10 kinds of people in this world... those who understand binary and those who don't.

I tell a version of that joke like this.-

there are three types of mathematicians in this world.  Those that can count and those that can’t.

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For the circle worshippers.....

12 is a nice number to have if you live in the time before calculators...

It gozinta 360, exactly 30 times. No decimals required.

Dozens, baker’s dozens, and lagniappe, an MS favorite, come to mind... :)

Alexa tried to write a joke about pi, but it went on forever...

Best regards,

-a-

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1 minute ago, Hank said:

I always heard that there are three kinds of people:  those who can count, and those who can't. 

Yeah, me too. Or me neither. Same difference, right? 

Hah!  Great minds think alike! You posted like 2 seconds ahead of me.

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2 minutes ago, carusoam said:

For the circle worshippers.....

12 is a nice number to have if you live in the time before calculators...

It gozinta 360, exactly 30 times. No decimals required.

Dozens, baker’s dozens, and lagniappe, an MS favorite, come to mind... :)

Alexa tried to write a joke about pi, but it went on forever...

Best regards,

-a-

I was trying to figure out what the units of at "gozinta" are....

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1 minute ago, Fred₂O said:

I was trying to figure out what the units of at "gozinta" are....

That's all part of cipherin', Jethro Bodine-style! Yeee-haawww!! Lessee, four gozinta twelve three times . . . .  :P

Edited by Hank
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