This sounds like you would want to convert the points to polar representation: https://code.jsoftware.com/wiki/User:Devon_McCormick/PolarCartesianConversion .
On Thu, Nov 16, 2023 at 9:47 AM 'PMA' via Programming < programm...@jsoftware.com> wrote: > Hi Henry, > > Chris Burke advised me to re-send my original question to this Forum. > > Sorry for the duplication. > > PA > > > On 11/16/23 09:39, PMA wrote: > > Thank you for these! Will pursue... > > > > PA > > > > On 11/16/23 09:26, Henry Rich wrote: > >> This is my reply to a question someone posed yesterday. This > >> afternoon I will post a complete solution. It's like the puzzle > >> problems I posed you, but just a little longer and comes from a real > >> user need. If you want to solve it yourself you will need the > >> primitives > >> > >> j. dyad, / monad, / dyad, ~, -. dyad, ^ monad, | dyad, -, /: dyad, *. > >> monad > >> > >> hhr > >> > >> On 11/15/2023 6:49 PM, Henry Rich wrote: > >>> I would find the angles from each point to each other point, take > >>> modulus(pi/2), concatenate the list with its negative, and sort. > >>> Rotation by each angle produces a new alignment. Only J primitives > >>> are needed. > >>> > >>> Use complex numbers to represent the (x,y) values, and *. to convert > >>> to angles. > >>> > >>> Henry Rich > >>> > >>> On 11/15/2023 5:52 PM, 'PMA' via Wiki wrote: > >>>> > >>>> Dear J-Wiki, > >>>> > >>>> I want to make a script that, given the X/Y values of a 2D > >>>> dot-graph, will rotate the graph around its designated origin, > >>>> looking for instances of 2 or more points coming into new > >>>> horizontal &/or vertical alignment, and at each such instance > >>>> output the full set of current X/Y values (integer-rounded). > >>>> > >>>> Could you point me to the main needed ingredients? > >>>> > >>>> Thanks in advance, > >>>> > >>>> Peter Armstrong > >>>> > >>> > >> > >> ---------------------------------------------------------------------- > >> For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- > 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
