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Macfreak7 · Mar 29, 2004, 05:15 AM

I have an idea about it but I'd like to know what an expert thinks?
So what is it and how do you get 3.1415926535897932384...
(wataru?)

(On a side note, damn Calc.app isn't precise enough)

Sealobo · Mar 29, 2004, 05:50 AM

If you can read those calculus & trig nonsense, you're then qualified to ask. Otherwise forget it.

AKcrab · Mar 29, 2004, 06:19 AM

Circumference/Diameter = Pi

Use any perfect circle, and do your own measurements. My dad had me use cans from the cupboard and a tape measure.

benb · Mar 29, 2004, 10:55 AM

Pi = SUMk=0 to infinity 16-k [ 4/(8k+1) - 2/(8k+4) - 1/(8k+5) - 1/(8k+6) ]

Shaddim · Mar 29, 2004, 10:58 AM

Originally posted by AKcrab:
Use any perfect circle, and do your own measurements.

Is that a trick comment? Perfect circle = impossible

gorickey · Mar 29, 2004, 10:58 AM

Screw Pi...it's all about Avogadro's Mole # of 6.02 x 10^23 that really matters...

Powaqqatsi · Mar 29, 2004, 11:29 AM

Originally posted by Macfreak7:
I have an idea about it but I'd like to know what an expert thinks?
So what is it and how do you get 3.1415926535897932384...
(wataru?)

(On a side note, damn Calc.app isn't precise enough)

You never learned this at school ?

wataru · Mar 29, 2004, 12:00 PM

There are many different ways to calculate pi, some better than others. Like someone said, though, the simplest answer is that it's the circumference/diameter of a circle. Kind of one of those interesting quirks of nature.

If you want to calculate it for yourself, you could try writing this simple program in the language of your choice: Make a grid of n squares and add up the area of those that fall within a unit circle (radius=1). Obviously you'll want n to be very large (making the squares very small). As n gets arbitrarily large the answer will converge to pi, but your accuracy will be limited by the size of the data structure you use.

There are plenty of resources on the web about pi. Here's a good one:
http://mathworld.wolfram.com/Pi.html

TubaMuffins · Mar 29, 2004, 01:42 PM

Originally posted by MacNStein:
Is that a trick comment? Perfect circle = impossible

what are you talking about? how can a perfect cirle be impossible?

mitchell_pgh · Mar 29, 2004, 01:57 PM

Originally posted by TubaMuffins:
what are you talking about? how can a perfect cirle be impossible?

It's more of a "to create a perfect circle is impossible"... there are always imperfections...

But that goes for about anything...

Eriamjh · Mar 29, 2004, 02:01 PM

3

d4nth3m4n · Mar 29, 2004, 02:15 PM

.

shunt · Mar 29, 2004, 02:36 PM

Originally posted by Macfreak7:
I have an idea about it but I'd like to know what an expert thinks?
So what is it and how do you get 3.1415926535897932384...
(wataru?)

(On a side note, damn Calc.app isn't precise enough)

Simply put it's a ratio of a circle's circumference to it's diameter. A way of relating two measurements to perform realworld applications of geometry. For example gear ratios in a transmission, etc. to calculate final drive rpm/speed and such.

Driven gear/Drive gear= Drive ratio ....connected to a tire that makes one revolution will mean the circumference=distance traveled

22/7 should ring a bell (again it's a ratio)

When you say 3.14...., it's still 3.14.../1

I used to like math, but now it hurts my brain.

eek....ups is here!!

mitchell_pgh · Mar 29, 2004, 02:41 PM

Originally posted by Eriamjh:
3

Hey, do you work at NASA as well... We decided it would save a considerable amount of time to simply round it down to 3. We considered 3.14, but we thought .14 was really close to 0, and that's like two whole more numbers... and with the economy the way it is, we need to cut wherever we can...

f1000 · Mar 29, 2004, 02:57 PM

Originally posted by shunt:
22/7 should ring a bell (again it's a ratio)

22/7 is an APPROXIMATION of Pi.

Pi cannot be completely represented by a ratio of integers.

shunt · Mar 29, 2004, 03:25 PM

Originally posted by f1000:
22/7 is an APPROXIMATION of Pi.

Pi cannot be completely represented by a ratio of integers.

No, the decimal equivalent is an approximation.

The value represented as a fraction is the most accurate, or so say some mathematicians.

olePigeon · Mar 29, 2004, 03:36 PM

Originally posted by gorickey:
Screw Pi...it's all about Avogadro's Mole # of 6.02 x 10^23 that really matters...

No, e is the most important once you hit trig and calc. Everyone loves logs!

Turias · Mar 29, 2004, 03:37 PM

Originally posted by shunt:
No, the decimal equivalent is an approximation.

The value represented as a fraction is the most accurate, or so say some mathematicians.

22/7 is approximately 3.14285714
pi is approximately 3.14159265

Close, but not close enough. If you have to approximate, it better to use a decimal to more than four significant digits.

olePigeon · Mar 29, 2004, 03:45 PM

n (sorry, it puts a questionmark when I put in Pi) is an exact value. It's as real as 1 or 10,000. Same with e

Millennium · Mar 29, 2004, 03:50 PM

Originally posted by shunt:
No, the decimal equivalent is an approximation.

The value represented as a fraction is the most accurate, or so say some mathematicians.

22/7 isn't even the most accurate representation out there as far as fractions go. For example, 223/71 is even closer, and 355/113 is closer still. And let us never forget 104348/33215...

shunt · Mar 29, 2004, 03:50 PM

My response to that is:

Brown truck came

Brown truck left

Yum, new hardware

OwlBoy · Mar 29, 2004, 03:51 PM

My friend remembers like the first 16 numbers of Pi...

Man.

-Owl

Sealobo · Mar 29, 2004, 04:14 PM

Pi is out of fashion. I remember there exist a cooler number starts with the letter T.... (Tau?)

Xeo · Mar 29, 2004, 04:14 PM

So is it true that

= 8.53973

?

benb · Mar 29, 2004, 04:16 PM

e is much cooler than pi.

e is so great. I love e.

d4nth3m4n · Mar 29, 2004, 04:34 PM

dont overdo it, youll be an e-tard then. no seriously, serotonin is a good thing.

OwlBoy · Mar 29, 2004, 04:36 PM

"I'm the Pie ****er!"

f1000 · Mar 29, 2004, 04:46 PM

Originally posted by shunt:
No, the decimal equivalent is an approximation.

The value represented as a fraction is the most accurate, or so say some mathematicians.

I never said that the decimal equivalent wasn't an approximation.

22/7 <> Pi.

Claiming that 22/7 is the MOST accurate is a nonsense statement. 22/7 is the most accurate among what: rational representations with a double digit numerator and single digit denominator?

voodoo · Mar 29, 2004, 05:02 PM

e is really cool, but I like Avogadros' mol much better. I think it is my favorite scientific number!

Pi is so yesterday man. They even made a movie or two named Pi.

awaspaas · Mar 29, 2004, 05:21 PM

Archimedes approximated pi by understanding that the circumference of a circle is somewhere between the perimeter of a polygon inscribed in a circle and a polygon circumscribed about a circle. He calculated the perimeters by making equations for the perimeter for n-sided polygons circumscribed and inscribed in circles. His approximation for pi using a pair of 96-sided polygons was quite accurate, and all without any calculators or even measuring devices.

(I went to the science museum on Saturday)

voodoo · Mar 29, 2004, 05:23 PM

Neeeeeeeeeeeeeeeeeeerd

benb · Mar 29, 2004, 05:40 PM

e is much better than the mol. So much more useful. Love the exponential function!

voodoo · Mar 29, 2004, 05:42 PM

Originally posted by benb:
e is much better than the mol. So much more useful. Love the exponential function!

Better is subjective but useful? Depends on what you are doing. If you are doing, say, chemistry you'll vote mol.

f1000 · Mar 29, 2004, 05:44 PM

Originally posted by Macfreak7:
I have an idea about it but I'd like to know what an expert thinks?
So what is it and how do you get 3.1415926535897932384...

Consider the following sequence of ones and zeros:

1.101001000100001000001...

Although this sequence of digits represents an irrational number, the sequence itself contains an obvious pattern.

The sequence of digits in Pi, on the other hand, has never been shown to form any kind of pattern. If the sequence of digits in Pi is truly RANDOM, then consider some of the following implications:

Let's set off the digits in Pi like this: Pi = 3. 14 15 92 65 35 89 79 32 38 ...

If we map letters, spaces, and punctuation symbols to each pair of digits above (like in ASCII), then given enough decimal places we would find words and even entire sentences among the gibberish.

Moreover, since Pi is infinite, we will find complete works of literature, such as sonnets, short stories, or even the Bible, within the sequence.

We can take it a step further by mapping the nucleotides G, A, T, C to each digit instead of the letters of the alphabet. Pi would then contain the DNA sequences of all life on Earth (dead, living, and yet to be born).

So what is Pi?

d4nth3m4n · Mar 29, 2004, 05:50 PM

yeah, but how unique is that for all irrational numbers? the example you gave was a little oversimplified.

WOULD pi contain all of that? or COULD pi contain all of that? just because its random does not mean it MUST be in there right? like the monkeys banging on typewriters coming up with hamlet thing... it could happen, but by no means WILL it.

</man im a stickler for language today>

Xeo · Mar 29, 2004, 05:50 PM

Originally posted by f1000:
Consider the following sequence of ones and zeros:

1.101001000100001000001...

Although this sequence of digits represents an irrational number, the sequence itself contains an obvious pattern.

The sequence of digits in Pi, on the other hand, has never been shown to form any kind of pattern. If the sequence of digits in Pi is truly RANDOM, then consider some of the following implications:

Let's set off the digits in Pi like this: Pi = 3. 14 15 92 65 35 89 79 32 38 ...

If we map letters, spaces, and punctuation symbols to each pair of digits above (like in ASCII), then given enough decimal places we would find words and even entire sentences among the gibberish.

Moreover, since Pi is infinite, we will find complete works of literature, such as sonnets, short stories, or even the Bible, within the sequence.

We can take it a step further by mapping the nucleotides G, A, T, C to each digit instead of the letters of the alphabet. Pi would then contain the DNA sequences of all life on Earth (dead, living, and yet to be born).

So what is Pi?

Given an infinite number of monkeys typing on an infinite number of typewriters, you're gonna have a lot of poop to deal with. Grab a shovel.

awaspaas · Mar 29, 2004, 05:51 PM

Originally posted by f1000:
If we map letters, spaces, and punctuation symbols to each pair of digits above (like in ASCII), then given enough decimal places we would find words and even entire sentences among the gibberish.

And it's searchable too...

http://www.angio.net/pi/piquery

awaspaas · Mar 29, 2004, 05:52 PM

Originally posted by d4nth3m4n:
yeah, but how unique is that for all irrational numbers? the example you gave was a little oversimplified.

WOULD pi contain all of that? or COULD pi contain all of that? just because its random does not mean it MUST be in there right? like the monkeys banging on typewriters coming up with hamlet thing... it could happen, but by no means WILL it.

</man im a stickler for language today>

If it's truly random and infinite, then it all MUST be there!

gorgonzola · Mar 29, 2004, 05:53 PM

Originally posted by shunt:
No, the decimal equivalent is an approximation.

The value represented as a fraction is the most accurate, or so say some mathematicians.

Pi is an irrational number, and irrationals can't be accurately represented as a ratio of integers. (Rationals are all numbers that can be expressed as a ratio of integers, such as 1.5 = 3/2.) And as Millennium said, 22/7 isn't very accurate at all.

Also, if you are talking about e and pi, a nice (and very famous) identity discovered by Euler is e^(i*pi) = -1 (which can be derived from e^(i*x) = cos(x) + i*sin(x); going further, this formula can be derived from the Taylor series expansions for e^x, sin(x), and cos(x)).

Turias · Mar 29, 2004, 05:56 PM

Originally posted by awaspaas:
If it's truly random and infinite, then it all MUST be there!

Prove it.

f1000 · Mar 29, 2004, 05:57 PM

Originally posted by d4nth3m4n:
yeah, but how unique is that for all irrational numbers? the example you gave was a little oversimplified.

WOULD pi contain all of that? or COULD pi contain all of that? just because its random does not mean it MUST be in there right? like the monkeys banging on typewriters coming up with hamlet thing... it could happen, but by no means WILL it.

</man im a stickler for language today>

It can be proven that it WILL happen by converting any sequence of characters (say, a sonnet) into a probability. This probability is ABSURDLY LOW, but it is still FINITE.

So if Pi is truly infinite and random, then all of these implications are true; however, nobody has proven that Pi is truly random, and doing so is not trivial.

As Xeon said, in the end, you're going to end up with a lot of dookie (but, who's to say what's dookie to us isn't Romeo & Juliet to aliens in the Gamma Quadrant?)

f1000 · Mar 29, 2004, 05:58 PM

Originally posted by awaspaas:
And it's searchable too...

http://www.angio.net/pi/piquery

AWESOME!!! I love this!

voodoo · Mar 29, 2004, 05:59 PM

Originally posted by awaspaas:
And it's searchable too...

http://www.angio.net/pi/piquery

My birthdate is not a part of the first million digits of Pi

Sealobo · Mar 29, 2004, 06:02 PM

Originally posted by awaspaas:
And it's searchable too...

http://www.angio.net/pi/piquery

This is cooler than cool. i found my cell phone #~!

Xeo · Mar 29, 2004, 06:09 PM

Originally posted by voodoo:
My birthdate is not a part of the first million digits of Pi

Mine is, and my 3 closest friends too. I used YYYYMMDD format.

f1000 · Mar 29, 2004, 06:24 PM

After decades of intense, groundbreaking work, number theorists have discovered that Pi is an enormous UUencoded binary.

The good news is they have figured out a way to decompress it.

The bad news is that it's a thirteen-dimensional JPEG of God giving us the finger.

awaspaas · Mar 29, 2004, 06:50 PM

Originally posted by Turias:
Prove it.

The probability of any number sequence being in a string of random numbers increases as the size of the number string increases. As n approaches infinity, the probability of finding your string approaches 1.

I don't know if it's proof, but good enough for me.

Turias · Mar 29, 2004, 06:54 PM

Originally posted by awaspaas:
The probability of any number sequence being in a string of random numbers increases as the size of the number string increases. As n approaches infinity, the probability of finding your string approaches 1.

I don't know if it's proof, but good enough for me.

But you first have to prove that the decimal string in pi is actually a sequence of random numbers. Good luck.

awaspaas · Mar 29, 2004, 07:02 PM

Originally posted by Turias:
But you first have to prove that the decimal string in pi is actually a sequence of random numbers. Good luck.

That's why I said "If it's truly random and infinite, then it all MUST be there"

Macfreak7 · Mar 29, 2004, 10:02 PM

Interesting comments by experts and non-experts.
I shall try writing that program (when I can) involving squares within a unit circle and I'm guessing that's where the trig. is involved as well, IF done geometrically.