What is Pi???

   For many centuries, man has wondered how to caluculate pi. Pi is an irrational number, meaning it can't be expressed as a fraction or a decimal number with and ending place. In other words, the decimals on pi just keep on going. Pi is sometimes known as Ludolph's Constant, because he spent his life calculating it out to the 35th decimal place. A rough fraction for pi is 22/7. This fraction is accurate by 0.04025%. A rough decimal calculation is 3.141592654.

The History of Pi

   The Babylonians found the first known value for Pi in around 2000BC -They used (25/8). An Egyptian scribe by the name of Ahmes wrote the earliest known record of pi. This document was called the Rhind Papyrus. The first person that started to ponder pi was the great Greek mathematician Archimedes. He inscribed a hexagon into a circle (as seen below) and he calculated pi for the hexagon, which was 3. He then used a dodecagon to calculate pi. He countinued to do this until he got to a 96-agon where pi was 3.1419.

Then the circle's circumference is twice the base length of the pyramid, and the circle's area is equal to the pyramid's vertical sectional area through the peak. The ratio of the perimeter of the base of the Great Pyramid to its height is twice Pi. The same ratio for the Pyramid of the Sun in Mexico is four times Pi. Both are built to an accuracy of a few inches.

   A Chinese mathematician by the name of Lui Hui took Archemedes' method a step farther. He used a 3,072-gon to find pi was about 3.1416. As time went on into the second millennium A.D., Sir Isaac Newton, with the help of others, invented what we call calculus. They used this type of math to calculate pi even further. To see some equations for pi used by these mathematicians, see this site Favorite Formulas for Pi

Program

Here is a program that will calculate Pi to the 32,000,000 decimal place. The credit for this fast pi calculatoring program goes to Dr. Kanada.

SuperPi.zip

Computer Records of Pi

Here is a listing of records held by computers for calculating pi.

1949 AD - ENIAC computes pi to 2,037 decimals in 70 hours
 

1955 AD - NORC computers 3,089 digits in 13 minutes
 

1959 AD - IBM 704 computer 16,167 places of pi
 

1961 AD - Daniel Shanks and John Wrench use IBM 7090 to find 100,200 places in 8 hrs
 

1966 AD - IBM 7030 finds 250,000 places
 

1967 AD - CDC 6600 finds 500,000 places
 

1973 AD - Jean Guilloud and M. Bouyer use CDC 7600 to get 1,000,000 places in 23.3 hrs
 

1983 AD - Y. Tamura and Y. Kanada use HITAC M-280H to get 16,000,000 places in less then 30 hrs
 

1988 AD - Kanda computes 201,326,000 digits on a Hitachi S-820 in 6 hrs
 

1989 AD - Chudnovsky brothers find 480,000,000 digits

                                  Kanda then finds 536,000,000 digits,

                                  Chudnovskys then find 1,000,000,000 digits
 

1995 AD - Kanda does it again! He finds 6,000,000,000 digits
 

1996 AD - Chudnovskys get over 8,000,000,000 digits
 

1997 AD - Kanada and Takahasi calculated 51,500,000,000 digits on a Hitachi  SR2201 in just over 29 hours.
 

Binary Pi

Pi does not have to be written in decimal (base 10) notation (3.14159265....). Here it is in binary (base 2) notation:

11.0010010000111111011010101000100010000101101000110000100011010011

You can do lots more stuff with Pi when it is in binary format - like drawing weird pictures of it, or even listening to it. As Pi has an infinite number of places, it is quite possible that any message you liked could be heard somewhere in Pi. It has even been suggested it contains the VOICE OF GOD. In Carl Sagan's book 'Contact' the places of Pi (in base 11) are found to contain a message from the beings that built the universe. 1