how to plot contours in matlab

I would like to make contours of elevations. My text file which contain lat, lon and elevation data set. I want to genterate contours of this elevation data set.on this help vedio and documentations i able to prepare this code as starting

a=load('2002dec.txt');
>> x=a(:,1);
y=a(:,2);
>> z=a(:,3);
>> [x,y]=meshgrid(60:0.5:78,21:0.5:38);
>> contour(x,y,z)

But getting error.

I also want to set a shape file as back ground of these contours.Any guide line will be highly appriciable.

My text file data and shape file has been attached with this post

Answer 1

[KSSV]

shapefile = 'PAK_adm1.shp' ;
S = shaperead(shapefile) ;
data = importdata('2002dec.txt') ;
x = data(:,1) ; x = unique(x) ;  
y = data(:,2) ; y = unique(y) ; 
z = data(:,3) ;
[X,Y] = meshgrid(x,y) ; 
Z = reshape(z,size(X)) ;

pcolor(Y,X,Z) ; shading interp ;
hold on
for i = 1:length(S)
    plot(S(i).X,S(i).Y,'k') ;

[Muhammad Usman Saleem]

Dear @Dr. Siva Srinivas Kolukula , what this code is doing? It is only producing color image consist on grids. Please tell me what kind of map it is? Whether these are another view to show contours?

Tell me please whether it is DEM?

[KSSV]

I mentioned already....use contour(Y,X,Z)....you will get the contours...

Answer 2

[KSSV]

You may use contour(Y,X,Z) for plotting contour....

Answer 3

[KSSV]

Try using freezeColors after hold on..... You may get the funciton from the link: http://in.mathworks.com/matlabcentral/fileexchange/7943-freezecolors---unfreezecolors