how to smooth the corners of a map

I have a map of this type generated with the command "contourf(XX,YY,ZZ);" where XX is the longitude value, YY is the latitude value and ZZ is the data to be entered. This map with the different colors is created based on a grid of points that are spaced from each other by one degree of latitude and one degree of longitude. For this reason, in some cases, the limits of these maps are very clear.

I wanted to ask : is there a way to create smoother edges? to make the limits of colors more curvilinear...

thanksss

Answer 1

[Chunru]

You can interpolate the data first before using contourf. For example, you can use scatteredInterpolant (with method "natural) if your grid is irregular; Or you can use griddedInterpolant (which has more exotic interpolation methods).

[ELISABETTA BILLOTTA]

oook, but I tried to use:

asmooth=scatterInterpolant(XX,YY,ZZ); XX-YY-ZZ are all 41x41 double

contourf(asmooth);

and I get this error "The input points must be specified in column-vector format."

how can I do?

[Chunru]

Do you have regular or irregular grids? Show some data of your XX and YY. Or you can try

asmooth=scatterInterpolant(XX(:),YY(:),ZZ(:))