Add regions of statistical significance to a map plot

Hello,

I am using the following to map out a trend in data over a region:

ax = worldmap(latlim, lonlim);
S = shaperead('landareas','UseGeoCoords',true);
surfacem(lat, lon, inpdata)
geoshow([S.Lat], [S.Lon],'Color','black');

This should be simple but I am not seeing fora with it. Is there any way to now add in a surfacem plot of a matrix holding p-values of the trends? I would like to simply add a cross where the corresponding cell in the p-value matrix is < 0.05.

Thanks!

Answer 1

[Chad Greene]

You'll find a few hatch filling functions on the File Exchange site. For example, the ones mentioned here.

Generally, to apply non-mapping toolbox plotting functions to maps, you'll need to do something like

[x,y] = mfwdtran(lat,lon); 
contourf(x,y,z)

and then you'd be able to use hatchfill as shown in the Pick-of-the-Week example.

[mashtine]

Thanks a lot Chad and so sorry for the late reply! I was away.

[mashtine]

Hi Chad,

I have run into a problem with mfwdtran. How would I apply this transformation with unequal vectors of lat and lon? My lat variable is 97x1 whereas my lon variable is 121x1. I am getting an error with mfwdtran because of this.

Many thanks!

[Chad Greene]

Try

[Lon,Lat] = meshgrid(lon,lat); 
[x,y] = mfwdtran(Lat,Lon);

[mashtine]

Thanks a lot Chad. That did the trick on the projection side of thing but now I do not think that findobj is finding any patches on my plot as hPatch1 returns a 0x0 GraphicsPlaceholder. I attached my script to see if you can make any sense as to why I am getting this error.

I am getting the error:

Index exceeds matrix dimensions.

Error in hatchfill (line 96)
hax = get(A(1),'parent');

and I believe that is the case because hPatch1 is empty as no patch handle was found.

You have been a big help thus far so thank you.

[mortain]

Hello,

I am getting the same error after updating to Matlab 2015.

Have you found a fix for this problem?

Cheers