Re: [Gnuplot-info] rtics NOT starting on 0 degrees

[Kevin O. <rko...@gm...>]

On Sun, Jul 12, 2020 at 1:40 PM theozh <th...@gm...> wrote:

> I'm not sure whether you can do this directly. I assume you mean the ttics.
> Although you can set a polar grid angle (check 'help grid') you can only
> start at multiples of 90 degrees. Check 'help theta'.
> A workaround would be to draw the gridlines manually.
> I hope this still helps somehow.
> Best, Theo.
>
> Try the following example:
>
> ### polar plot with grids
> reset session
> set size square
> set angle degrees
>
> set polar
> set theta clockwise top
> unset border
> unset tics
> unset raxis
> unset key
> set border polar
> set ttics 11.25, 22.50 format ""
> set rtics 10 scale 0 format ""
> set grid rtics
>
> set rrange[0:40]
> # manually draw grid lines
> do for [i=1:16] {
>     set arrow i from 0,0 to polar (i*360/16+11.25),40 lw 0.5 dt 3 lc rgb
> "black" nohead
> }
>
> set samples 16
> plot t/9 w lp pt 7 lc rgb "red"
> ### end of code
>
Thank you, Theo. I have not tried drawing the grid, but your suggestions
have gotten me very close to what I'm looking for. Especially for 'set
theta" and the use of "format" on set ttics". Since the manual for ttics
explicitly stated "The angular position is always labeled in degrees.", I
didn't even try format. As a result, I now am close to my goal. Still a
couple of things I need to tweak... like playing with the smoothing.

Again, thanks! If you are curious, it's at
http://ykoberman.mooo.com/display-weather-graph.pl?Plot=dir
Not too interesting unless you live near Lawrence Livermore National Lab,
but it's all gnuplot except the main page (Home).
--
Kevin Oberman, Part time kid herder and retired Network Engineer
E-mail: rko...@gm...
PGP Fingerprint: D03FB98AFA78E3B78C1694B318AB39EF1B055683