%Load Data
load fisheriris;
%The variable meas contains measurements on the sepal length, sepal width,
%petal length, and petal width for 150 iris specimens from the
%following three species :
labels = unique(species);
disp(labels);
%Train a Linear Discriminant Analysis (LDA) Classifier
mdl = ClassificationDiscriminant.fit(meas,species);
%Predict Species Using the LDA Model
predicted_species = predict(mdl,meas);
%Compute and Visualize the Confusion Matrix
Conf_Mat = confusionmat(species,predicted_species);
disp(Conf_Mat);
%We can visualize the same using a heat map.
h = heatmap(Conf_Mat);


confMat=Conf_Mat;
%%% précision

for i =1:size(confMat,1)

    precision(i)=confMat(i,i)/sum(confMat(:,i));

end

Precision=sum(precision)/size(confMat,1);
disp(Precision);
%%% recall

for i =1:size(confMat,1)

    recall(i)=confMat(i,i)/sum(confMat(i,:));

end
Recall=sum(recall)/size(confMat,1);
disp(Recall);
%%% F-score

F_score=2*Recall*Precision/(Precision+Recall); %%F_score=2*1/((1/Precision)+(1/Recall));
disp(F_score);