Hello Hakan Caldag,
From what I gather, you have multiple 2D histogram datasets that you want to plot together by overlaying them on top of one another, with each dataset represented using a different color map.
You can plot the histograms overlaid by plotting them on separate axes and then aligning the axes together. The transparency can be adjusted by changing the ‘AlphaData’ of the plots using the “alpha” function. A lower ‘AlphaData’ value will result in a more transparent plot.
The following code snippet plots two histograms in a single plot, with each histogram represented by a custom color map and one of the histograms being transparent:
% Load data
data = load('2d_hist_data.mat');
edges = data.edges;
counts = data.counts;
vec = [100; 83; 68; 30; 15; 0];
N = 128;
% Define color maps
hex_colors_blue = [
'#ffffff'; % White
'#e6f0ff'; % Light blue
'#cce0ff'; % Lighter blue
'#99c2ff'; % Light blue
'#3399ff'; % Medium blue
'#0066cc' % Dark blue
];
raw_blue = sscanf(hex_colors_blue', '#%2x%2x%2x', [3, size(hex_colors_blue, 1)]).' / 255;
map_blue = interp1(vec, raw_blue, linspace(100, 0, N), 'pchip');
hex_colors_red = [
'#ffffff'; % White
'#ffe6e6'; % Light red
'#ffcccc'; % Lighter red
'#ff9999'; % Light red
'#ff3333'; % Medium red
'#cc0000' % Dark red
];
raw_red = sscanf(hex_colors_red', '#%2x%2x%2x', [3, size(hex_colors_red, 1)]).' / 255;
map_red = interp1(vec, raw_red, linspace(100, 0, N), 'pchip');
% Plot the two histograms
figure;
% Create two axes
ax1 = axes;
s1 = imagesc(edges(1), edges(2), counts);
view(2);
ax2 = axes;
s2 = imagesc(edges(1), edges(2), counts');
% Link them together
linkaxes([ax1, ax2]);
% Hide the top axes
ax2.Visible = 'off';
ax2.XTick = [];
ax2.YTick = [];
% Give each one its own colormap
colormap(ax1, map_blue);
colormap(ax2, map_red);
alpha(s2, 0.4);
% Add colorbars and get everything lined up
set([ax1, ax2], 'Position', [.17 .11 .685 .815]);
cb1 = colorbar(ax1, 'Position', [.05 .11 .0675 .815]);
cb2 = colorbar(ax2, 'Position', [.88 .11 .0675 .815]);
For further understanding, kindly refer to the following MathWorks Documentation:
- Refer to the ‘Description’ section to understand the relevant input methods and their effects: MathWorks Documentation.
I hope you find the above explanation and suggestions useful!
