MATLAB: How to plot the different values in a matrix as different entities in a single plot

matrixmoving plotplot

Here's my matrix:
1  3  4  4  1
3  1  2  4  3
4  2  1  2  2
2  4  4  4  1
2  2  3  4  4
I want to plot 1 as a red circle, 2 as a blue square and so on. Also, the values in my matrix keep changing after every iteration. I would like my plot to also change accordingly. Any help would be appreciated. Thanks!

Best Answer

This plots the row- and column-subscripts, each with the appropriate marker and color.
The Code —
M = [1  3  4  4  1
    3  1  2  4  3
    4  2  1  2  2
    2  4  4  4  1
    2  2  3  4  4];
for k1 = 1:max(M(:))
    I{k1} = find(M == k1);                                  % Linear Indices For Each Value
end
mc = {'or', 'sb', 'gp', 'c^'};                              % Colors & Markers
figure
hold all
for k1 = 1:max(M(:))
    [r,c] = ind2sub(size(M), I{k1});                        % Convert Linear Indices To Subscripts
    plot(c, r, mc{k1})                                      % Plot Appropriate Markers At Subscripts
end
axis([0  size(M,2)+1    0  size(M,1)+1])                    % Set Axis Limits
set(gca, 'XTick',1:size(M,2), 'YTick',1:size(M,1))          % Define Tick Values
set(gca, 'YDir','reverse')
xlabel('Column Index')
ylabel('Row Index')
legend('1', '2', '3', '4', 'Location','EastOutside')
As ‘M’ changes, you will have to re-run it, probably in a loop or as a function called in a loop, with ‘M’ as the argument.
The Plot —
EDIT — Axis limits and tick values now change with thge size of ‘M’, added the legend.
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