how do i display zeros in confusion chart?

In confusion chart the cells correspond to zero values are getting blank which is normal for matlab...but i need to show these zero values...is there any way?

Answer 1

[Udit06]

Hi Arnab,

To display zeros instead of blank spaces, you can create a confusion matrix and display it using a heatmap while ensuring that all values, including zeros, are visible. You can find the code for the same below:

numSamples = 100;
numClasses = 5;

% Generate random true labels and predicted labels
trueLabels = randi([1, numClasses], numSamples, 1);
predictedLabels = trueLabels; % assigning predictLabels as trueLabels so that the confusion matrix contain some zeros

% Compute the confusion matrix
confMat = confusionmat(trueLabels, predictedLabels);

% Create a heatmap for the confusion matrix
h = heatmap(confMat, 'ColorbarVisible', 'off');

h.Colormap = [1 1 1];  % White

h.CellLabelColor = 'black';  % Ensure labels are visible
h.CellLabelFormat = '%d';    % Display as integers

% Add titles and labels for clarity
h.Title = 'Confusion Matrix';
h.XLabel = 'Predicted Class';
h.YLabel = 'True Class';

h.XDisplayLabels = string(1:numClasses);
h.YDisplayLabels = string(1:numClasses);

You can refer to the following MathWorks documentation to understand more about the heatmap function:

https://www.mathworks.com/help/matlab/ref/heatmap.html

I hope this helps.

Answer 2

[Mike Croucher]

This functionality is now available in MATLAB R2026a. You can get a confusionchart to show zeros using the ZerosVisible property.

g1 = [3 2 2 3 1 1]';	% Known groups
g2 = [4 2 3 NaN 1 1]';	% Predicted groups
C = confusionmat(g1,g2)

C = 4×4

2 0 0 0 0 1 1 0 0 0 0 1 0 0 0 0

<mw-icon class=""></mw-icon>

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confusionchart(C,ZerosVisible="on")