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Computing Pi decimals on HP 41; error in algorithm? - Vincent G - 09-30-2016 02:29 PM
Years ago, there was a discussion on the old forum about computing Pi to many decimals using an HP 41 ( see http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv015.cgi?read=72865 ). My vintage 41 sees very little use, but I have an emulator running on a different machine and recently got a DM-41 which does a decent job, and tried to run that program. The result I get for the claimed value of Pi is this: register 01: 31415.92653 02: 58979.32384 03: 62643.38327 04: 89456.42639 <-- error 05: 38033.96091 (...) The answer, according to published value of the number, should have been 01: 31415.92653 02: 58979.32384 03: 62643.38327 04: 95028.84197 <-- clearly different from that point onwards 05: 16939.93751 (...) Notice how the 4th register reading is completely off? I checked the published code (in the old forum) several times, and cannot find a fault in the way I entered it. Can anyone try it and check if the answer matched the real value, or the one I get? And if the later, how come it was never spotted before? RE: Computing Pi decimals on HP 41; error in algorithm? - Dieter - 09-30-2016 06:29 PM
(09-30-2016 02:29 PM)Vincent G Wrote: Years ago, there was a discussion on the old forum about computing Pi to many decimals using an HP 41 ( see http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv015.cgi?read=72865 ). FTR: I copied the listing from the old forum's post and converted it into a raw file which then was used in V41. In Turbo mode the program finished quickly, and here is the result: Yes, it's the same as yours. R01..03 are fine, then the result is off. Dieter |