Plot colored grid with transparency and overlay

Hello all,

I'm looking for a way to plot an n x m x 3 matrix to recreate the following type of graph:

the 3rd dimension will be global grids of data which range between 0-1. What I would like to do:

find a plot call where I can plot a global grid of the first dimension (with transparency and a specific color, say red), hold on, and then overly the next dimension and so forth so that I can view a gradient of the combination of all three factors.

If any of you have any ideas about how to approach this I would be very grateful. Thanks!

Answer 1

[Chad Greene]

The simplest way I can think of is to concatenate the three variables as individual RGB values and display as an image like this:

% Some fake data: 
[lon,lat] = meshgrid(-179:2:179,89.5:-1:-89.5); 
temp = mat2gray(peaks(180)); % mat2gray normalizes 0 to 1
sun = cosd(lat); 
water = abs(sind(lon)); 

% Optional: mask out the ocean: 
ocean = ~landmask(lat,lon); 
temp(ocean) = NaN; 
sun(ocean) = NaN; 
water(ocean) = NaN; 

% Concatenate 3 variables as rgb: 
im = cat(3,temp,sun,water); 

% Plot: 
worldmap('world')
geoshow(lat,lon,im)

Above I used my landmask function.