How to plot a 2D filled colour contour plot depth profile?

Hi all,

I have a 3D matrix named SALT which is of 90x90x50 size. Here, 90x90 is latitude/longitude information and 50 is salinity informatin in each ocean layer depth. I want to plot an intersected salinity contour profile like this -

The intersection will go through the middle of the map, or anywhere according to my choice. I have attached the 3D matrix in this question. Can anyone please help me out here?

Any feedback will be greatly appreciated!!

Answer 1

[Voss]

load SALT

s = permute(SALT(35,:,:),[3 2 1]);
contourf(s)

set(gca(),'YDir','reverse')
xlabel('Longitude(?) Index')
ylabel('Depth Index')
title('Salinity Profile at Latitude(?) #35')
ylabel(colorbar(),'Salinity')

[Ashfaq Ahmed]

Great! I actually did some brain storming and ended up with this plot -

I used these lines of code -

%% Salinity
clr = flipud(brewermap(15,'BrBG'));
clri= interp1(1:1:15,clr,1:0.25:15,'linear');

figure(1),clf;
n = 1;
t = tiledlayout(1,3);
t.TileSpacing = 'tight';
t.Padding = 'compact';

xIdx = 30;
yIdx = 75;

% Plotting
nexttile
contourf(rot90(rot90(SALT(:,:,1))),150,'edgecolor','none'); shading interp; 
colormap(gca, clri);
set(gca,'color',[0.55 0.55 0.55]);
line([xIdx, xIdx], [1, 90], 'Color', 'b', 'LineWidth', 4); hold on;
line([1, 90], [yIdx, yIdx], 'Color', 'r', 'LineWidth', 4); hold on;
set(gca, 'GridLineStyle', '-', 'MinorGridLineStyle', ':', 'LineWidth', 3);
box on; set(gca, 'GridLineStyle', '-','LineWidth', 3);
hold on; set(gca, 'Layer', 'top');
xlabel('x-index'); ylabel('y-index')
set(gca,'XTickLabel'); set(gca,'YTickLabel'); 
set(gca,'FontSize', 15)
title('Intersection line on Arctic')


nexttile
% Extract the salinity profile at the chosen latitude
salinityProfile = squeeze(SALT(:,90-xIdx,:));
salinityProfile =salinityProfile';
salinityProfile = fliplr(salinityProfile);
contourf(salinityProfile,15,'edgecolor','k','linewidth',1.5);
colormap(gca, clri)
set(gca, 'YDir', 'reverse');
set(gca,'color',[0.55 0.55 0.55])
set(gca, 'GridLineStyle', '-', 'MinorGridLineStyle', ':', 'LineWidth', 3);
box on; set(gca, 'GridLineStyle', '-','LineWidth', 3);
hold on; set(gca, 'Layer', 'top');
title('Salinity with depth (blue intersect)'); 
set(gca,'XTickLabel',[]); set(gca,'YTickLabel'); 
ylabel('Depth (m)');
set(gca,'FontSize', 15)

nexttile
% Extract the salinity profile at the chosen latitude
salinityProfile = squeeze(SALT(90-yIdx,:,:));
salinityProfile =salinityProfile';
salinityProfile = fliplr(salinityProfile);
contourf(salinityProfile,15,'edgecolor','k','linewidth',1.5);
colormap(gca, clri)
set(gca, 'YDir', 'reverse');
set(gca,'color',[0.55 0.55 0.55])
set(gca, 'GridLineStyle', '-', 'MinorGridLineStyle', ':', 'LineWidth', 3);
box on; set(gca, 'GridLineStyle', '-','LineWidth', 3);
hold on; set(gca, 'Layer', 'top');
title('Salinity with depth (red intersect)'); 
set(gca,'XTickLabel',[]); set(gca,'YTickLabel'); 
ylabel('Depth (m)');
set(gca,'FontSize', 15)
set(gcf, 'Position', [-2348,775,1403,476]);



c = colorbar;
c.FontSize = 15;
c.FontWeight = 'bold';
c.Layout.Tile = 'east';

I had a relevant quetsion. As you can see I had to use the same lines for the plotting repeatedly. Can I make them a plotting function and reduce my coding lines significantly? Can you help me ouit here? @Voss

[Voss]

Yes, you can make a function, but a loop may be good enough:

load SALT

%% Salinity
clr = flipud(parula(15));
clri= interp1(1:1:15,clr,1:0.25:15,'linear');

figure(1),clf;
n = 1;
t = tiledlayout(1,3);
t.TileSpacing = 'tight';
t.Padding = 'compact';

xIdx = 30;
yIdx = 75;

% Plotting
nexttile
contourf(rot90(rot90(SALT(:,:,1))),150,'edgecolor','none'); shading interp; 
colormap(gca, clri);
set(gca,'color',[0.55 0.55 0.55]);
line([xIdx, xIdx], [1, 90], 'Color', 'b', 'LineWidth', 4); hold on;
line([1, 90], [yIdx, yIdx], 'Color', 'r', 'LineWidth', 4); hold on;
set(gca, 'GridLineStyle', '-', 'MinorGridLineStyle', ':', 'LineWidth', 3);
box on; set(gca, 'GridLineStyle', '-','LineWidth', 3);
hold on; set(gca, 'Layer', 'top');
xlabel('x-index'); ylabel('y-index')
set(gca,'XTickLabel',[],'YTickLabel',[]); 
set(gca,'FontSize', 15)
title('Intersection line on Arctic')


data = {SALT(:,90-xIdx,:) SALT(90-yIdx,:,:)};
names = {'blue' 'red'};

for ii = 1:numel(data)
    
    nexttile
    % Extract the salinity profile at the chosen latitude or longitude
    salinityProfile = squeeze(data{ii});
    salinityProfile =salinityProfile';
    salinityProfile = fliplr(salinityProfile);
    contourf(salinityProfile,15,'edgecolor','k','linewidth',1.5);
    colormap(gca, clri)
    set(gca, 'YDir', 'reverse');
    set(gca,'color',[0.55 0.55 0.55])
    set(gca, 'GridLineStyle', '-', 'MinorGridLineStyle', ':', 'LineWidth', 3);
    box on; set(gca, 'GridLineStyle', '-','LineWidth', 3);
    hold on; set(gca, 'Layer', 'top');
    title(sprintf('Salinity with depth (%s intersect)',names{ii})); 
    set(gca,'XTickLabel',[],'YTickLabel',[]); 
    ylabel('Depth (m)');
    set(gca,'FontSize', 15)
    
end

set(gcf, 'Position', [-2348,775,1403,476]);

c = colorbar;
c.FontSize = 15;
c.FontWeight = 'bold';
c.Layout.Tile = 'east';