Request: Books/articles about history of early computing (pre 1950)

12312018, 08:42 AM
Post: #20




RE: Request: Books/articles about history of early computing (pre 1950)
(12302018 08:02 PM)pier4r Wrote: A Survey of Eniac Operations and Problems 19461952Nice find! ENIAC took 70 hours over a holiday weekend in 1949 to calculate just over 2000 digits of pi  it only had 200 digits of memory, so the calculation repeatedly streamed inputs from and output to punched cards. Half the time was spent in checking each operation by calculating the inverse. (ENIAC was originally a hardwired machine, but by sacrificing a factor of six in the speed it had been modified to fetch instructions from ROMs intended for use as function lookup tables. Each digit of the ROM was a tenposition rotary knob. I don't know how big the pi program was. I think the information can be found, behind a paywall.) Part of the motivation was to see how evenly spread the digits of e and pi are: e is unusually even whereas pi looks more like random digits. (As it turns out, the two calculations were very thorough proofs of reliability too.) Original paper can be seen, in part, at http://goo.gl/LuOUnb and some accessible information at http://www5.wittenberg.edu/news/2013/03_14_pi.html By 1983 you could buy a PC/XT, and if you'd had the 125byte program found here you could compute over 9000 digits at a rate of about 32 digits per minute. If you have IEEE access you may be able to read a paper about the ENIAC calculation at http://doi.ieeecomputersociety.org/10.1109/MAHC.2011.61 There's a popular writeup here too: https://www.pocketlint.com/laptops/news...niacfirst 

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