Plotting rose diagram at specific geographic location

Hi There,
Does GMT have the functionality to plot rose diagrams at specific geographic locations on a map? The documentation seems to indicate that it cannot do so, but I just want to double-check. Thanks!

The rose module can be plotted anywhere you want, but I think you are asking if it has an option to place it or center it at a given longitude/latitude. None of the modules have that specific option, but you can script that by having a list of locations where you want to plot things, mapproject them to plot coordinates, and use those positions in -X -Y.

Hi Paul,
Thanks for your reply. The method that you proposed works, but I find that it is the lower-left corners of the rose diagrams, not the centers, that are placed at the desired locations. Is there a way to center the rose diagrams? Thanks a lot!

No, you will have to subtract half the radius from x0 and y0.

Thanks. In addition, is there a way to plot rose diagrams with completely no plot boundaries or grid lines? When I use the command without -B it still plots the grid lines every 45º. Thanks a lot!

I think it shouldn’t do it. Try with -B0

The -B0 option still plots the frame.

Try -B+n
That should have no frames while -B0 means no annotations

-B+n still plots a circular frame.

Ah, I can understand that, psrose does its own farme and may not listen to -B+n. If you dont mind, please find a bug report on the GitHub Issue site.

I just did it. Thanks!

Hi everyone,

I have been trying to plot rose diagrams on Mercator projection. Then I found this very helpful topic.

First I used “mapproject” command to convert “lon lat” to xy coordinates. I think, I did this correctly with following command,

gmt mapproject data.dat -R25/46/35/43 -JM24c > tmp.dat

After that I plot rose diagrams in a kind of a loop as following command,

gmt psrose azimuth.log -R0/40/0/360 -S0.5c -A10 -L -Bxg20 -Byg60 -Gred -W0.5 -B+n -K -O -Xa$xx -Ya$yy >>

xx and yy is the corresponding X and Y values in tmp.dat obtained with “mapproject” command.

The problem is that rose diagrams are not located at perfectly true locations, there is some kind of shifting for locations.

Do you see any mistakes in the commands or thinking way?
What would be the reason for an offset on locations of rose diagrams?