Plotting chemical 2d reaction in different colors

WIlling to make an image of a 2D reaction of mixing the reagents "A+B=C".

On input have Matrix A and B, velocites, pressures, calculated Stoke's, solved for Pressure and velocities, obtainted moving reagents A B, then calculated C matrix from reaction.

So far came up to this (images 2 and 3, please disregard the first Image):

contourf(x,y,C',20,'k:'); 
contourf(x,y,A.'+B.',20,'k-');

Question is to how to combine images 2 and 3 with different colours to display output on a single image, i.e. e.g. Red for A, Blue for B and Green for C and white for background.

If you have problems accesing the GIF file below here is a video link of current result

[BALAJI KARTHEEK]

use hold on command

[Ulan Kelesbekov]

does not work for image() and contour() funciton, it overwrites the previous.

Answer 1

[darova]

What about alpha? Try to set transparency to your object and then just plot them together

[X1,Y1,Z1] = peaks(20);
[X2,Y2] = meshgrid(1:10);
R2 = hypot(X2,Y2);

h1 = surf(X2,Y2,Y2);
h2 = surface(5+X1,5+Y1,Z1/10);
% set([h1 h2],'edgecolor','none')
alpha 0.5
zlim([-1 1])
axis vis3d
for i = 1:100
    Z2 = sin(R2+i/10)./R2;
    set(h1,'zdata',Z2)
    set(h2,'zdata',Z1/10*(50-i)/100)
    pause(.1)
end

[Ulan Kelesbekov]

alpha seems not to work for countourf, it is suggested to enter manually for flat plot :(

[darova]

try to manually change using handles

[x,y,z] = peaks;
z1 = 10*sin(2*hypot(x,y))./hypot(x,y);
[~,h1] = contourf(x,y,z);
hold on
[~,h2] = contourf(x,y,z1);
hold off
h11 = get(h1,'children');
h22 = get(h2,'children');
set(h11,'facealpha',0.5)
set(h22,'facealpha',0.5)

Answer 2

[Ayush Gupta]

This problem can be tackled using the following approach. Suppose contour1.jpg is the first contour and cntour2.jpg is the second contour, the images can be superimposed using the given piece of code:

figure1 = figure; 

ax1 = axes('Parent',figure1); 

ax2 = axes('Parent',figure1); 

set(ax1,'Visible','off'); 

set(ax2,'Visible','off'); 

[a,map] = imread('contour1.jpg'); 

I = imshow(a,'Parent',ax2); 

alpha = 0.5; 

set(I,'AlphaData',alpha); 

imshow('contour2.jpg','Parent',ax1);