Haw can convert categories array to array of numeric or logical ?

I am creating a neural network in MATLAB,but i got this error

Error using nntraining.setup>setupPerWorker (line 96)

Targets T{1,1} is not numeric or logical.

outputFolder= fullfile(tempdir, '');
rootFolder = fullfile(outputFolder, '');
categories = {'2', '1', '0'};
imds = imageDatastore(fullfile(rootFolder, categories), 'LabelSource', 'foldernames');
numImageCategories = size(categories(imds.Labels),1);   % get category labels
 [trainingDS,validationDS] = splitEachLabel(imds,0.7,'randomize'); % generate training and validation set
 LabelCnt = countEachLabel(imds);                        % load lable information

p=[];
t1=[];
[l,m]=size(trainingDS.Files);

for q=1:l
    
    im1=readimage(trainingDS,q);
    im=double( im1);
    [r,c]=size(im)
    
       p11=[];
       for i=1:r
        for j=1:c
        p11=[p11;im(i,j,1)];
        end
       end
  p=[p p11];
  t1=[t1 trainingDS.Labels(q)];
  t = categories(t);
end
% % %  %% Multilayer backpropagation neural network
% % % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 net=newff(minmax(p), [4096 5 1], {'logsig','logsig','logsig'}, 'traingdx');
 [net,tr,Y,E,Pf,Af]=train(net,p,t);
 net

[Walter Roberson]

Try passing in categorical(t)

[dziri halima]

i got this error

Error using nntraining.setup>setupPerWorker (line 96)

Targets T is not a matrix or cell array.

[dziri halima]

when i use t=categories(t) i obtain t (1*147 cell)

[Walter Roberson]

Then do not use

categories = {'2', '1', '0'};

Use

categories = [2,1,0];

[dziri halima]

I can't change it because it uses to define each folder category.

Error using imageDatastore (line 125)

Cannot find files or folders matching: 'C:\Users\DELL\AppData\Local\Temp\'.

Error in clasifiersector (line 20)

imds = imageDatastore(fullfile(rootFolder, categories), 'LabelSource', 'foldernames');

[Walter Roberson]

Sigh. Then

t = char(categories(t(:))) - '0';

[dziri halima]

Unable to use a value of type 'cell' as an index.

Error in clasifiersector (line 83)

t = char(categories(t(:))) - '0';

[Walter Roberson]

Where do you assign to t to be able to use it in the line

t = categories(t);

? You have been building up t1 but not t.

[dziri halima]

I made a mistake in her writing, but nothing change .

t = categories(t1);

[dziri halima]

@Walter Roberson thank you sir ,i solved this problem.