TOKYO, Japan -- Shigeru Kondo, a Japanese systems engineer and Alexander J. Yee, an American computer science student, have calculated the value of pi to five trillion digits - setting the new world record for the Most digits of pi calculated.
"Alexander provided software and I was in charge of hardware. We couldn't have achieved the results without either of us," Kondo said, adding that the two men worked together while communicating by email.
Shigeru Kondo, a 55-year-old systems engineer for a food company based in northern Japan, easily surpassed the previous record of 2.7 trillion digits, set late last year by a French engineer.
Pi, the ratio of a circle's circumference to its diameter, starts with 3.14159 in a string whose digits are believed to never repeat or end.
Ten decimal places of p are sufficient to give the circumference of the Earth to a fraction of an inch, and thirty decimal places would give the circumference of the visible universe to a quantity imperceptible to the most powerful microscope. Simon Newcomb (1835-1909)
It took 90 days to calculate pi at Kondo's home using a desktop computer with 20 external hard disks. It ran on the operating system Windows Server 2008R2 and used powerful Intel microprocessors; it has a hard-drive capacity of 32 terabytes. Verification took 64 hours.
Kondo built the computer by himself, procuring parts from local electronics shops and via the Internet. "I don't really want to say how much it cost me as my family may hear it... it's about 18,000 dollars," he told AFP by telephone.
The mammoth calculation nearly came to grief on more than one occasion, Mr Kondo said, including one morning when his daughter tripped a circuit breaker when she turned a hair dryer on. The project was saved when the computer switched to an emergency 10-minute back-up power source.
Mr Kondo was also forced to remove casings from the computer and blow cool air onto the machine with fans as the temperature in his home rose to 40 degrees in the hottest Japanese summer since 1946.
It was midnight in Japan when the computer reached five trillion decimal places. "I was alone in the room at the moment... I know this is nothing but self satisfaction," he said. His mother and wife who live with him were sleeping at that time and later showed "no particular feelings" despite his sense of achievement, he said.
The previous Guinness World Record was set earlier this year by Fabrice Bellard, who calculated the value of pi to 2.7 trillion digits.
"Alexander provided software and I was in charge of hardware. We couldn't have achieved the results without either of us," Kondo said, adding that the two men worked together while communicating by email.
Shigeru Kondo, a 55-year-old systems engineer for a food company based in northern Japan, easily surpassed the previous record of 2.7 trillion digits, set late last year by a French engineer.
Pi, the ratio of a circle's circumference to its diameter, starts with 3.14159 in a string whose digits are believed to never repeat or end.
Ten decimal places of p are sufficient to give the circumference of the Earth to a fraction of an inch, and thirty decimal places would give the circumference of the visible universe to a quantity imperceptible to the most powerful microscope. Simon Newcomb (1835-1909)
It took 90 days to calculate pi at Kondo's home using a desktop computer with 20 external hard disks. It ran on the operating system Windows Server 2008R2 and used powerful Intel microprocessors; it has a hard-drive capacity of 32 terabytes. Verification took 64 hours.
Kondo built the computer by himself, procuring parts from local electronics shops and via the Internet. "I don't really want to say how much it cost me as my family may hear it... it's about 18,000 dollars," he told AFP by telephone.
The mammoth calculation nearly came to grief on more than one occasion, Mr Kondo said, including one morning when his daughter tripped a circuit breaker when she turned a hair dryer on. The project was saved when the computer switched to an emergency 10-minute back-up power source.
Mr Kondo was also forced to remove casings from the computer and blow cool air onto the machine with fans as the temperature in his home rose to 40 degrees in the hottest Japanese summer since 1946.
It was midnight in Japan when the computer reached five trillion decimal places. "I was alone in the room at the moment... I know this is nothing but self satisfaction," he said. His mother and wife who live with him were sleeping at that time and later showed "no particular feelings" despite his sense of achievement, he said.
The previous Guinness World Record was set earlier this year by Fabrice Bellard, who calculated the value of pi to 2.7 trillion digits.
