Yeah, I guess it should be fine to just look at the sequence to see if it's converging, or test the result.
My thought was that iterations are cheap, I just wanted a small finite number of them. Thanks, -- Raul On Sun, Jan 28, 2018 at 6:05 PM, Henry Rich <[email protected]> wrote: > If Newton's method converges, you won't need a couple of hundred rounds - > just a dozen or so. > > Henry Rich > > > On 1/28/2018 5:52 PM, Skip Cave wrote: >> >> Raul, >> >> You had it right in the first place. >> >> 0 = 8 + (2^x) - 2^2^x NB. Is correct, and the answer is real >> >> The answer is close to 1.75379 >> >> I wanted to know how to construct the Newton Raphson method using the >> iteration verb N described in the link: http://code.jsoftware. >> com/wiki/NYCJUG/2010-11-09 >> under "A Sampling of Solvers - Newton's Method" >> >> N=: 1 : '- u % u d. 1' >> >> Skip >> >> >> >> >> >> Skip Cave >> Cave Consulting LLC >> >> On Sun, Jan 28, 2018 at 4:38 PM, Raul Miller <[email protected]> >> wrote: >> >>> Eh... I *think* you meant what would be expressed in J as: >>> >>> 0 = 8 + (2^x) - 2^2^x >>> >>> I'd probably try maybe a few hundred rounds of newton's method first, >>> and see where that leads. >>> >>> But there's an ambiguity where the original expression (depending on >>> the frame of reference of the poster) could have been intended to be: >>> >>> 0 = 8 + (2^x) + _2^2^x >>> >>> [if that is solvable, x might have to be complex] >>> >>> Thanks, >>> >>> -- >>> Raul >>> >>> On Sun, Jan 28, 2018 at 5:25 PM, Skip Cave <[email protected]> >>> wrote: >>>> >>>> What is the best iterative way to solve this equation: >>>> >>>> (-2^2^x) + (2^x) +8 =0 >>>> >>>> >>>> Skip Cave >>>> Cave Consulting LLC >>>> ---------------------------------------------------------------------- >>>> For information about J forums see http://www.jsoftware.com/forums.htm >>> >>> ---------------------------------------------------------------------- >>> For information about J forums see http://www.jsoftware.com/forums.htm >> >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm > > > > --- > This email has been checked for viruses by AVG. > http://www.avg.com > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
