Presumably you're working with an older version of J, like J807. (J9 tossed the D. conjunction and requires we use the math/calculus library manually.)
Anyways, if you increase the size of the plot, you'll see that the display artifact you're looking at is a consequence of discretization -- the plot is composed of lines and at that particular point in the graph these lines do not adequately conform to the underlying curve. FYI, -- Raul On Thu, Nov 24, 2022 at 1:01 PM 'Bo Jacoby' via Programming <programm...@jsoftware.com> wrote: > > plot|:^@-@-:@^&2"0 D.(i.3)10%~50-~i.101 > > > NB. The blue curve is the bell curve. Mean value = 50. Standard deviation = > 10NB. The read curve is the derivative of the blue curve. It crosses Y=0 at > X=50NB. The green curve is the derivative of the red curve. It crosses Y=0 at > X=50-10 and X=50+10 > NB. But why is the green curve so ugly around X=50? > Thank you! > Bo. > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
