How can I display a 2D binary matrix as a black & white plot?
Date: 2022-07-14 11:23:37
I have a 2D binary matrix that I want to display as a black and white plot. For example, let's say I have a 4-by-4 matrix as follows:
1 1 0 1
0 0 1 0
1 1 0 1
1 0 0 0
How can this be plotted as a black and white matrix? Some of my input binary matrices are of size 100-by-9, so I would ideally need a solution that generalizes to different sized matrices.
Answers:
If you want to make a crossword-type plot as shown here (with grid lines and black and white squares) you can use the imagesc function, a gray colormap, and modify the axes properties like so:
mat = [1 1 0 1; 0 0 1 0; 1 1 0 1; 1 0 0 0]; % Your sample matrix
[r, c] = size(mat); % Get the matrix size
imagesc((1:c)+0.5, (1:r)+0.5, mat); % Plot the image
colormap(gray); % Use a gray colormap
axis equal % Make axes grid sizes equal
set(gca, 'XTick', 1:(c+1), 'YTick', 1:(r+1), ... % Change some axes properties
'XLim', [1 c+1], 'YLim', [1 r+1], ...
'GridLineStyle', '-', 'XGrid', 'on', 'YGrid', 'on');
And here's the image you should get: