How to extract data from nc file by using shape file in MATLAB

How to extract data from nc file by using shape file in matlab. I am sending a sample .nc file of resolution 1*1 degree and shapefile of India.

[Tanmoyee Bhattacharya]

Sir files are attached.

[Walter Roberson]

Nothing was attached

[Tanmoyee Bhattacharya]

Sir file is attached.

Answer 1

[KSSV]

    clc; clear all ;
    file = 'cpc_rfe_v2.0_sa_dly.bin.20020101.nc' ;
    lon = ncread(file,'lon') ;
    lat = ncread(file,'lat') ;
    RF = ncread(file,'RF') ;
    %
    path = [pwd filesep 'India State wise with telangana' filesep 'india27-11.shp'] ;
    S = shaperead(path) ;
    n = length(S) ;
    pcolor(lon,lat,RF') ; shading interp ;
    hold on
    for i = 1%:n
       x = S(i).X ; y = S(i).Y ;
       rfi = interp2(lon,lat,RF',x,y) ;
    end

Your next question is: 'I want data along the polygon, not along the boundary'. It is a project work and you expect everything online?

[Muhammad Usman Saleem]

@KSSV dear, will you tell me how can i get data along the complete polygon ?

Answer 2

[Jitesh Dadich]

this really helped me....

Dear @KSSV, what if the time is also given in the nc file i.e. nc data are in 3D...then how will we extract the data from .nc file according to given shapefile....

[Jitesh Dadich]

and can we save the output in .nc format file..?

[KSSV]

Read about inpolygon.

[ANKUR KUMAR]

@Jitesh Refer to my answer.

Answer 3

[ANKUR KUMAR]

You can use maskregion function, which mask out the data as per your shapefile.

Example you can refer to for your convenience

W=shaperead('us_states.shp');

[data_cropped]=maskregion(lon,lat,data,W);

contourf(lon,lat,nanmean(data_cropped,3)','linecolor','none')

For cropping the data, you can use cropregion.

[Saumya Singh]

Hi Ankur,

tried maskregion function, but the output produces matrix of same dimension with all values as NaN. Its not working.

[ANKUR KUMAR]

Could you please attach the mat file, along with the shape file?

[Saumya Singh]

@ANKUR KUMAR

Sure.

Thanks.

[Saumya Singh]

here is the shapefile

[Suraj]

hi saumya did u find the solution while using the maskregion!