Pepe, I was able to compare the "domain"-induced viewrgb with the wikipedia version and I see the difference you noted. Was that example an attempt at addressing my question about where lines of finite length can be drawn for this case? I ask that because you used the phrase "at that line".
On Tue, May 15, 2018 at 6:50 PM, Jose Mario Quintana < [email protected]> wrote: > I am glad to hear that it runs on JQt/Linux. It also seems to run on JHS > (at least it works with a Kindle Paperwhite 3 running on JHS/Linux > (BusyBox) using a custom J interpreter). > > You might find the following clumsy verb useful, > > domain=. |.@|:@({.@[ + ] *~ j./&i.&>/@+.@(1j1 + ] %~ -~/@[))&>/ > > It produces the vertices of a square grid corresponding to (the lower and > upper points of) a given complex interval and resolution; for example, > > In particular, > > viewrgb 12 ccEnhPh zetahat"0 domain _20j_30 20j30 ; 0.1 > > reproduces, to some extent, the first graph on the Wikipedia page for the > Riemann zeta function. The leftmost section of the graph produced by J > looks suspicious and might indicate that Ewart's default approximation > (zetahat) breaks down at that point (or rather, at that line). > > > > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
