Monday, March 19, 2012

Pi Day: How the 'Irrational' Number Pushed the Limits of Computing

Government Computer News (03/14/12) William Jackson 

The challenge of determining the value of Pi has helped push the envelope of computing. "It has played a role in computer programming and memory allocation and has led to ingenious algorithms that allow you to calculate this with high precision," says mathematician Daniel W. Lozier, retired head of the mathematical software group in the U.S. National Institute of Standards and Technology's Applied and Computational Mathematics Division. "It's a way of pushing computing machinery to its limits." Memory is crucial in executing calculations, as are techniques for calculating efficiently, given the large strings of numbers involved. The calculation of Pi to longer and longer number strings has improved along with the advancement of computers, and the current record-holder is Japan's T2K Supercomputer, which calculated the value to 2.6 trillion digits in about 73 hours and 36 minutes. That marks a considerable upgrade from the ENIAC computer's 1949 estimation of Pi to 2,037 digits, which took 70 hours. Ten years later an IBM 704 was able to calculate Pi to 16,157 places in four hours and 20 minutes. "Pi serves as a test case for mathematical studies in the area of number theory," Lozier notes.