Upon looking a little more at the page - http://zenwerx.com/projects/pi-digits/pi/
mentioned in the post below, I was amused to note that the last 138 of the 4,194,304 places of pi displayed on that page are random and/or wrong. Problems begin about decimal place 4194166 which is shown as 9 but should be 7. I suppose such errors are not very high up on the list of misrepresentations on web pages, but in my case it caused a smile and memory of an event that took place some 40 years ago. Jeffery Shallit ( http://www.cs.uwaterloo.ca/~shallit/ ) was a summer intern at the IBM Philadelphia Scientific Center in 1972 (I think). He was working on some high precision computations using APL. I can't remember whether it was a precise evaluation of pi to several thousand places, or perhaps Mersenne prime #24 ( _1 + 2^19937x ) - but in any case, Jeffery had succeeded in printing out this lengthy number, and left a copy of the pages of digits on several people's desks. The next morning, Ron Frank came in, looked at the copy on his desk, circled a digit towards the end of the long number and wrote, "Are you sure about this digit?" and put it back on the Desk Jeff was using. That afternoon, Jeff came in and discovered the note and raced into Ron's office saying, "How do you know that digit is wrong??" To which Ron calmly replied, "I have no idea if it is correct or not - I was just asking if you were sure...." I was (am still) impressed with Jeffery's work because he did it in an 80Kbyte APL workspace. Hard to imagine these days when it is routine to work with a hundred thousand times that much memory.... Although I note that J only consumes 80704 bytes to calculate _1 + 2^19937x that's impressive too. I've copied Jeffery on this note, and wish I had an address to pass my memory past Ron. In my experience, it seems likely to me that either they wouldn't have any memory of such an event, or might have versions quite different from my memory. It is strange/interesting how our memories work. On 2012/05/08 09:44 , Joey K Tuttle wrote: > Being a fan of things pi, I'm wondering about several things in your post. > > The URL you give points to a site purporting to have 4 (not 50) million > digits of pi. Maybe I missed a pointer to a larger dataset. > > > > On 2012/05/08 03:56 , Joe Bohart wrote: > > I've load 50 million integer digits of pi and trying to do a moving average > on them. > > NB. data from http://zenwerx.com/projects/pi-digits/pi/ > NB. used perl to write each digits on 1 line of file data > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
