Contour maps from lat-lon?

Hi to everyone

I need to create contour maps of parameter T (temperature) from a grid of type

Latitude    Longitude    T
42.44567    12.457393    25.3
...         ...          ...

I also have a shapefile to put as bakground of these maps.

I don't need to interpolate with a complex algorithm the values, because the grid contained in the file comes from an interpolation algorithm and it is very thick (250 m of resolution). So, it is enough to use something like the inverse of the square of distance to plot the contour maps.

Because I am new in matlab world, can someone give me some tips for starting?

the final objective is obtaining something like this:

Thank you

Answer 1

[Aravind Ravikumar]

Hey, you could use the contour() function (documentation here). More specifically you can use, countour(X,Y,Z) with Latitude as X, Longitude as Y, T as Z. You can also add title to your figure (documentation here).

You can use mapshow() (documentation here) with shaperead() (documentation here) to load your shapefile. You can overlay the figures with hold on or you could try something like this.

[Andrea Cecilia]

Hi,

I've tried to give

contour(Lat,Lon,T);

where Lat, Lon, T are nx1 arrays containing double values. It gives me the following error:

Error using contour (line 48)
Z must be at least a 2x2 matrix.

[Joy Wingrave]

I have the same problem, did you find a soluion?

[Alfred Ruff]

Hi did anlyone manage to solve this problem ?

im trying to plot wind speed against Lat and Long

Answer 2

[darova]

• Use griddata to create matrix data
• Use contour