I try to let the laptop identify an increase in any vakue of a heatmap grid and if the value increase then that grid will be converted to green but I couldnt let that work.

%here's the code I use for testing but whenever I run the code the numbers that didn't increase also convert into green

clearvars;
x = 15;
y = 15;
matrix = randi([0, 3], x, y);
previousMatrix = matrix;
h = heatmap(matrix);
colorbar;
cmap = [linspace(0, 0, 256)' linspace(0, 1, 256)' linspace(1, 0, 256)'];
colormap(cmap);
h.ColorLimits = [0, 5];

for iteration = 1:10
    rowToChange = randi(x);
    colToChange = randi(y);
    roll = randi([1, 6]);
    fprintf("Dice Roll: %d\n", roll);
    oldValue = matrix(rowToChange, colToChange);
    matrix(rowToChange, colToChange) = matrix(rowToChange, colToChange) + roll;
    
    if matrix(rowToChange, colToChange) > oldValue
        matrix(rowToChange, colToChange) = 5;
    end
    
    % Only re-create the heatmap here after making the updates
    h = heatmap(matrix);
    colormap(cmap);
    h.ColorLimits = [0, 5]; % Ensure only cells with value 5 are highlighted
    previousMatrix = matrix;
    pause(1);
end

Answer 1

[Shashi Kiran]

Hi @Haoyan,

I have reviewed your code and have a few observations:

• In the code segment below, consider a scenario where the old value is 2, and the roll value is 1 (the minimum possible). When you add the roll value to the old value, the result is 3, which will always be greater than the old value.
• Consequently, the `if` block is always executed, causing the color to change to green regardless.

roll = randi([1, 6]); % 1
oldValue = matrix(rowToChange, colToChange); % 2
matrix(rowToChange, colToChange) = matrix(rowToChange, colToChange) + roll; % 3

if matrix(rowToChange, colToChange) > oldValue
    matrix(rowToChange, colToChange) = 5;
end

Please review this logic. Let me know if I can assist you further.