how to show my output data in map.

10 views (last 30 days)
devendra
devendra on 10 Jun 2014
Commented: Srishti Gaur on 3 May 2018
sir i want to plot my own output data in map.please help me. how will do this.sir i have 8 years annual time series of rainfall frequency and sir my data size is (20x22x8)(lon,lat,time).
thank you in advance.please sir help me.

Accepted Answer

Kelly Kearney
Kelly Kearney on 12 Jun 2014
Edited: Kelly Kearney on 12 Jun 2014
I reaally shouldn't be giving you the answer, since you've shown absolutely no effort to create this plot yourself. But I'm bored at work waiting for some simulations to finish, so it's your lucky day.
First of all, I'm assuming that you already have a shapefile holding the India boundary, and that you have a raster grid of x (lon), y (lat), and z coordinates. Also, I'm assuming that your data grid isn't already trimmed to the India borders.
So, the first quick-and-dirty way to do this is to simply mask the data points outside the border:
file = 'TM_WORLD_BORDERS-0.3.shp';
S = shaperead(file, 'usegeocoords', true, 'selector', ...
{@(x) strcmp(x,'India'), 'NAME'});
x = linspace(min(S.Lon), max(S.Lon), 100);
y = linspace(min(S.Lat), max(S.Lat), 100);
[x,y] = meshgrid(x,y);
z = rand(100);
isin = inpolygon(x,y,S.Lon,S.Lat);
z2 = z;
z2(~isin) = NaN;
figure('color','w');
worldmap('India');
pcolorm(y,x,z2);
plotm(S.Lat, S.Lon, 'k');
You'll notice that things get a little jagged around the edges, though. You can get a cleaner map by plotting all the data, then overlaying it with a polygon that masks out all but your region of interest. (Or in this case, polygons, since neither geoshow nor patchm tend to play well with polygons with holes):
lnlim = [65 100];
ltlim = [5 40];
lt = linspace(ltlim(1), ltlim(2), 3);
ln = linspace(lnlim(1), lnlim(2), 3);
for ii = 1:2
ltbox{ii} = lt([1 2 2 1 1]'+(ii-1));
lnbox{ii} = ln([1 1 2 2 1]'+(ii-1));
end
[lnmask, ltmask] = deal(cell(2));
for ii = 1:2
for jj = 1:2
[lnmask{ii,jj}, ltmask{ii,jj}] = polybool('-', ...
lnbox{ii}, ltbox{jj}, S.Lon, S.Lat);
end
end
ltboxall = ltlim([1 2 2 1 1]);
lnboxall = lnlim([1 1 2 2 1]);
[lnmaskall, ltmaskall] = polybool('-', lnboxall, ltboxall, S.Lon, S.Lat);
figure('color','w');
worldmap('India');
pcolorm(y,x,z);
for ii = 1:4
patchm(ltmask{ii}, lnmask{ii}, 'w', 'edgecolor', 'none');
end
plotm(ltmaskall, lnmaskall, 'k');
  9 Comments
Srishti Gaur
Srishti Gaur on 3 May 2018
Dear Kelly Kearney, How to make multiple sub-plots for the same? I tried but it not able to do. Thank you

Sign in to comment.

More Answers (3)

David Sanchez
David Sanchez on 10 Jun 2014
you could take a look at the demos within Matlab documentation. You will find many working examples on data representation, like this one:
z=peaks(25);
surf(z);
colormap(jet);
Adapt your data to any of those examples.
  5 Comments
devendra
devendra on 10 Jun 2014
sir there is not necessary that high-resolution map but problem is that how to do this thing.

Sign in to comment.


David Sanchez
David Sanchez on 11 Jun 2014
You will have to present your data by year:
XX YY]= meshgrid(X1,Y1);
z=ltm(:,:,1);
surf(XX,YY,z')
xlabel('XX')
ylabel('YY')
view([0 90])
  11 Comments
devendra
devendra on 12 Jun 2014
geoshow('map.shp', 'FaceColor', [0.9 0.9 0.9])
this code is polting india map but i have no idea about next step. i also read about contourfm function but how will use this for my output data i have no idea.

Sign in to comment.


peterhack
peterhack on 11 Nov 2016
As I have a question on the above example I will utilize this thread, hope that is alright. I am using the presented code to mask the data points outside the border. Works fine so far. However, I want to use the DisplayType surface. Thus I am using geoshow to plot the data. Unfortunately it does not fill the whole map within the borders as a buffer is left. Any hint?
file = 'TM_WORLD_BORDERS-0.3.shp';
S = shaperead(file, 'usegeocoords', true, 'selector', ...
{@(x) strcmp(x,'India'), 'NAME'});
x = linspace(min(S.Lon), max(S.Lon), 100);
y = linspace(min(S.Lat), max(S.Lat), 100);
[x,y] = meshgrid(x,y);
z = rand(100);
isin = inpolygon(x,y,S.Lon,S.Lat);
z2 = z;
z2(~isin) = NaN;
lnlim = [65 100];
ltlim = [5 40];
lt = linspace(ltlim(1), ltlim(2), 3);
ln = linspace(lnlim(1), lnlim(2), 3);
for ii = 1:2
ltbox{ii} = lt([1 2 2 1 1]'+(ii-1));
lnbox{ii} = ln([1 1 2 2 1]'+(ii-1));
end
[lnmask, ltmask] = deal(cell(2));
for ii = 1:2
for jj = 1:2
[lnmask{ii,jj}, ltmask{ii,jj}] = polybool('-', ...
lnbox{ii}, ltbox{jj}, S.Lon, S.Lat);
end
end
ltboxall = ltlim([1 2 2 1 1]);
lnboxall = lnlim([1 1 2 2 1]);
[lnmaskall, ltmaskall] = polybool('-', lnboxall, ltboxall, S.Lon, S.Lat);
figure('color','w');
worldmap('India');
geoshow(y, x, z2, 'DisplayType','surface')
contourcmap('jet',min(z):1:max(z),'colorbar','on','location','horizontal')
for ii = 1:4
patchm(ltmask{ii}, lnmask{ii}, 'w', 'edgecolor', 'none');
end
plotm(ltmaskall, lnmaskall, 'k');

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!