Combine two seperate matrices into a 3d matrix.

Lets say I have a matrix R and a matrix B. These matrices are X*Y and I want to combine them both so they are a multidimensional matrix so I can show the new matrix as an image. How do I do this? I tried using this F=cat(3,R,B); figure(2) image(C)

But I get an error/

Answer 1

[Image Analyst]

image can take a 3D image with 3 color channels, not two. If you want the green channel to be zero, then concatenate a zero matrix

rgbImage = cat(3, R, zeros(size(R), 'uint8')), B);
image(rgbImage);