Thanks William for your suggestions! I was able to get grey/gray lines following your instructions.
But getting dashed lines seem to be not straightforward for the polar maps because the circumferential lines are defined with mp_graticule. Or maybe I didn't get it from your reply.
It is easy to define the line numbers to be different colors:
ppl color,LINE_NUMBER,R,G,B
LINE_NUMBER will be 1-6 (unless you are using SET MODE LINECOLORS; see the documentation).
R,G,B are values from 0-100
Gray might be 50,50,50
The line numbers circulate after 6: 7 is thicker black, 8 is thicker red, ..., 13 is even thicker black, etc.
Unpredictable results can occur if you redefine a line color within a single plot! That's what MODE LINECOLORS is for.
If you want to make white lines, use RGB values of 99,99,99, not 100. Maybe this bug has been fixed, but using RGB values 100,100,100 used to crash Fprint.
To make dashed lines (with the PLOT command):
plot/.../dash=(down1,up1,down2,up2) variable
where down means "draw this length line", up means "leave this blank space".
PyFerret gives even more control.
Billy
> On Jun 27, 2019, at 5:17 AM, Claude-Michel Nzotungicimpaye <miklonzo.science@xxxxxxxxx> wrote:
>
> Dear Ferreters,
>
> I'd like to have grey/gray and ideally dashed circumferential and transect lines for the attached "polar" maps, which I created following this example. I can get red, green, blue, etc. continuous lines by putting 2, 3, 4, etc. after the command used to generate the circumferential and transect lines (ie. go mp_graticule 0 360 45 40 90 20). But, please how can I get these lines to be grey/gray and dashed?
>
> Thanks in advance,
> <polar_wetmaps.png>