How do I change the colors of a matrix image?

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I have a script that will generate a 12x12 matrix of ones and zeros. When I create an image from this the default colours are yellow for one and blue for zero. I want to change this to white for zero and red for one.
Can anyone help me?
Thanks,
Joe
m = zeros(12, 12);
numIterations = 1800;
row = ones(1, numIterations);
col = ones(1, numIterations);
m(row(1), col(1)) = 1;
imagesc(m);
axis('on', 'image');
percentage = 0.40; % 20% of time will be the same
for k = 2 : numIterations
if rand(1) < percentage
% 20% of the time it will stay in the same place.
row(k) = row(k-1);
col(k) = col(k-1);
else
% 80% of the time it will select a new place.
% First get a tentative new location.
row(k) = row(k-1) + randi([-1,1], 1);
col(k) = col(k-1) + randi([-1,1], 1);
while row(k) == row(k-1) && col(k) == col(k-1) || row(k) <= 0 || row(k) > size(m, 1) || col(k) <= 0 || col(k) > size(m, 2)
% Get a new location.
row(k) = row(k-1) + randi([-1,1], 1);
col(k) = col(k-1) + randi([-1,1], 1);
while row(k) <= 0 || row(k) > size(m, 1)
row(k) = row(k-1) + randi([-1,1], 1);
end
while col(k) <= 0 || col(k) > size(m, 2)
col(k) = col(k-1) + randi([-1,1], 1);
end
end
end
m(row(k-1), col(k-1)) = 0; % Clear old location
m(row(k), col(k)) = 1; % Set new location
imagesc(m);
grid on;
caption = sprintf('At Iteration %d, Row = %d, Column = %d', k, row(k), col(k));
title(caption, 'FontSize', 15);
drawnow;
pause(0.8)
end

Accepted Answer

Ameer Hamza
Ameer Hamza on 25 May 2020
Edited: Ameer Hamza on 25 May 2020
Use colormap
imagesc(m);
colormap([1 1 1; 1 0 0])
grid on;
  2 Comments
Image Analyst
Image Analyst on 25 May 2020
How does this give white background with a red square?
Ameer Hamza
Ameer Hamza on 25 May 2020
Oh! That was a mistake. Thanks for pointing out.

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