I want to create random bumps on a flat surface
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    Daniel Gray
 on 17 Jul 2017
  
    
    
    
    
    Commented: AMERA ANJUM
 on 23 May 2020
            I have a 300x300 zeros matrix and I would like to create random bumps on the surface on random heights. To be more detailed, imagine circles of ones on the surface, I would like to (rather than those) have bumps on the surface.
Almost like 3D Guassian bumps on the surface.
Any help would be appreciated.
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Accepted Answer
  Grzegorz Knor
      
 on 17 Jul 2017
        M = zeros(300,300); % initial matrix
N = 3; % number of bumps
sigma = 3;% std (width) of Gauss 
maxAmplitude = 5; % maximum height
[x,y] = meshgrid(1:size(M,1),1:size(M,2));
for k=1:N
    % random location of bumps
    xc = randi(size(M,1));
    yc = randi(size(M,2));
    % Gauss function
    exponent = ((x-xc).^2 + (y-yc).^2)./(2*sigma^2);
    amplitude = rand()*maxAmplitude;  
    % add Gauss to the matrix M
    M = M + amplitude*exp(-exponent);
end
surf(M)
shading interp
2 Comments
  AMERA ANJUM
 on 23 May 2020
				Daniel Sir
On generation of random bumps at random locations of random amplitudes on the flat surface, do shrinkage of the flat surface area from the edges can be seen. So that over all area on bumping and debumping remains to be same. Please do reply
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