How to plot the confusion matrix of more than 2 classes?

2 次查看（过去 30 天）

Munshida P 2020-2-13

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/505230-how-to-plot-the-confusion-matrix-of-more-than-2-classes

评论： Bhaskar R 2020-2-13

clc
clear
% Load Image dataset
faceDatabase = imageSet('facedatabaseatt','recursive');
%splitting into training and testing sets
[training,test] = partition(faceDatabase,[0.8 0.2]);
% Extract HOG Features for training set 
featureCount = 1;
for i=1:size(training,2)
    for j = 1:training(i).Count
        trainingFeatures(featureCount,:) = extractHOGFeatures(read(training(i),j));
       % imshow(read(training(i),j));
        %pause(0.0011);
        trainingLabel{featureCount} = training(i).Description;    
        featureCount = featureCount + 1;
    end
    personIndex{i} = training(i).Description;
end
% Create 40 class classifier
faceClassifier = fitcknn(trainingFeatures,trainingLabel);
%testing
kk=1;
for person=1:40
    for j = 1:test(person).Count
        queryImage = read(test(person),j);
        queryFeatures = extractHOGFeatures(queryImage);
        actualLabel = predict(faceClassifier,queryFeatures);
        actualLabel=char(actualLabel);
        predictedLabel=test(person).Description;
        
        
        al(kk)=str2num(actualLabel(2:length(actualLabel)))
        pl(kk)=str2num(predictedLabel(2:length(predictedLabel))) 
        kk=kk+1;
       % Map back to training set to find identity
        %booleanIndex = strcmp(actualLabel, personIndex);
        %integerIndex = find(booleanIndex);
    end    
end
if isempty(al)==0
    accuracy=length(find(pl==al))/size(test,1)
end