I'm using what is given in the essay, trying to change as little as possible. However the polynomial version is more straightforward.
On Fri, Jan 15, 2021 at 11:10 PM Henry Rich <[email protected]> wrote: > A reasonable expectation. sslope_jcalculus_ provides an approximation > to the slope. A user could write a conjunction to use that if > deriv_jcalculus_ can't find a closed-form derivative. > > But: #.&1 _1 _2&> opens its argument. Can there ever be a derivative of > a boxed argument? > > Henry Rich > > On 1/15/2021 10:48 PM, Devon McCormick wrote: > > I guess I was expecting a numerical solution if a symbolic one is not > found. > > > > On Fri, Jan 15, 2021 at 10:05 PM Henry Rich <[email protected]> > wrote: > > > >> What do you expect the derivative of #.&1 _1 _2&> to be? > >> > >> I see that #.&1 _1 _2 has no derivative, but 1 _1 _2&p. does. > >> > >> Deficiencies in math/calculus are not 'issues'. They are opportunities > >> for improvement by users. > >> > >> Henry Rich > >> > >> On 1/15/2021 9:37 PM, Devon McCormick wrote: > >>> I tried to update chapter 23 of the "50 Shades of J" essay using the > new > >>> version of Newton's method from " > >>> https://code.jsoftware.com/wiki/Essays/Newton%27s_Method"; but this > >> breaks > >>> examples in "50 Shades", e.g. > >>> > >>> f1=: #.&1 _1 _2&> NB. Function to use > >>> Newton=: adverb : ']-u % (u deriv_jcalculus_ 1' > >>> f1 Newton 1 > >>> |domain error: deriv_jcalculus_ > >>> | 13!:8(3) > >>> |deriv_jcalculus_[:19] > >>> > >>> Is this a known issue? > >>> > >>> I've left my "fix" in as the existing code will also break in the > current > >>> version of J. > >>> > >> > >> -- > >> This email has been checked for viruses by AVG. > >> https://www.avg.com > >> > >> ---------------------------------------------------------------------- > >> For information about J forums see http://www.jsoftware.com/forums.htm > >> > > > > > -- > This email has been checked for viruses by AVG. > https://www.avg.com > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > -- Devon McCormick, CFA Quantitative Consultant ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
