How to extract data through the shapefile (India) from global precipitation data.

YOu need to read about inpolygon. This function helps you to extract what you want.

shapefile = 'India_Shapefile\ind_state_2000.shp' ;

S = load('global_data.mat') ;
C = shaperead(shapefile) ;
N = length(C) ;

lon = S.lon ; lat = S.lat ;
P = S.prc ;
[X,Y] = meshgrid(lon,lat) ;

iwant = cell(N,2) ;
for i =1:N

      Cx = C(i).X ; Cy = C(i).Y ;
      idx = inpolygon(X(:),Y(:),Cx',Cy') ;
      P1 = P(:,:,1)' ;
      iwant{i,1} = P1(idx) ;
      P2 = P(:,:,2)' ;
      iwant{i,2} = P2(idx) ;
  end