how to solve this error "Undefined function 'crossvalind' for input arguments of type 'char'" while running below code in matlab 2019a

%% Evaluate Accuracy
load('Accuracy_Data.mat')
Accuracy_Percent= zeros(200,1);
for i = 1:500
data = Train_Feat;
%groups = ismember(Train_Label,1);
groups = ismember(Train_Label,0);
[train,test] = crossvalind('HoldOut',groups);
cp = classperf(groups);
%svmStruct =svmtrain(data(train,:),groups(train),'showplot',false,'kernel_function','linear');
svmStruct = fitcsvm(data(train,:),groups(train),'showplot',false,'kernel_function','linear');
%classes = svmclassify(svmStruct,data(test,:),'showplot',false);
classes = predict(svmStruct,data(test,:),'showplot',false);
classperf(cp,classes,test);
Accuracy = cp.CorrectRate;
Accuracy_Percent(i) = Accuracy.*100;
end
Max_Accuracy = max(Accuracy_Percent);
sprintf('Accuracy of Linear Kernel with 500 iterations is: %g%%',Max_Accuracy)

[Walter Roberson]

crossvalind() requires the Bioinformatics Toolbox. Do you have that installed and licensed?

Answer 1

[Gagan Baishya]

Hello,

cvIndices = crossvalind(cvMethod,N,M)

returns the indices cvIndices after applying cvMethod on N observations using M as the selection parameter.

In your code, the third parameter is missing which is probably causing the issue. Try specifying the selection parameter (M) to avoid the error.

For better understanding, please go through the documentation link below: https://in.mathworks.com/help/bioinfo/ref/crossvalind.html#:~:text=evaluation%20each%20time.-,%27HoldOut%27,-M%20is%20the