Color Plot In Descending Order

I have a matrix such as [x1 y1 z1; x2 y2 z2 ... xn yn zn]. I am plotting it as follows

ptCloud = pointCloud(plot_mat);

How can I add on a color matrix (in grayscale) such that the max z value is white and lowest color value is black. So far I have tried to use a colormap but the colormap only does concentration of points and not min and max.

[Image Analyst]

Please attach plot_mat in a .mat file so people can try some things. In the meantime, try the caxis() function.

Answer 1

[Sushmitha Kudari]

canyon = load('INIT.MAT')
topo = canyon.siocanyon;

%%%%%%%%%%%%%load with Munk profile%%%%%%%%%%%%%%%%%%%%
 munkProfile = load('MunkS_500Hz.shd.mat'); 
 pressureWave = munkProfile.pressure; 
 pressureWave = abs(pressureWave); 
 squished = squeeze(pressureWave);
 logged = log(squished);
 
 
 [X,Y]=ndgrid(1:size(logged,1),1:size(logged,2 ));
 
 
 Z = ones(size(logged));  
 
 plot_mat = [X(:) Y(:) logged(:)];
 
 [remove, ~] = find(plot_mat(:,3) == -Inf); 
 plot_mat(remove,:) = []; 
 
 ptCloud = pointCloud(plot_mat);
 
 figure
 pcshow(ptCloud);
 cmap = colormap(gray); 
 
 

Here is what I have tried. Init file is linked here.