I can't how to Predict my data

this is mya coding

FOR TRAINING data = xlsread('berhasil',2,'K11:N2048');

% Proses Normalisasi Data

max_data = max(max(data));

min_data = min(min(data));

[m,n] = size(data);

data_norm = zeros(m,n); for x = 1:m

    for y = 1:n

        data_norm(x,y) = 0.1+0.8*(data(x,y)-min_data)/(max_data-min_data);

    end

end

% Proses membaca data latih dari excel

filename = 'berhasil.xlsx';

sheet = 2;

xlRange = 'O409:R2038';

Data = xlsread(filename, sheet, xlRange);

data_latih = Data(:,1:3)';

target_latih = Data(:,4)';

[m,n] = size(data_latih);

% Pembuatan JST

net = newff(minmax(data_latih),[20 1],{'logsig','purelin'},'traingdx');

% Memberikan nilai untuk mempengaruhi proses pelatihan

net.performFcn = 'mse';

net.trainParam.goal = 0.01;

net.trainParam.show = 25;

net.trainParam.epochs = 1000;

net.trainParam.mc = 0.95;

net.trainParam.lr =0.1;

% Proses training

[net_keluaran,tr,Y,E] = train(net,data_latih,target_latih);

% Hasil setelah pelatihan

bobot_hidden = net_keluaran.IW{1,1};

bobot_keluaran = net_keluaran.LW{2,1};

bias_hidden = net_keluaran.b{1,1};

bias_keluaran = net_keluaran.b{2,1};

jumlah_iterasi = tr.num_epochs;

nilai_keluaran = Y;

nilai_error = E;

error_MSE = (1/n)*sum(nilai_error.^2);

save net.mat net_keluaran

% Hasil prediksi

hasil_latih = sim(net_keluaran,data_latih);

max_data = 4;

min_data = 1;

hasil_latih = ((hasil_latih-0.1)*(max_data-min_data)/0.8)+min_data;

% Performansi hasil prediksi

filename = 'berhasil.xlsx';

sheet = 2;

xlRange = 'K11:N1024';

target_latih_asli = xlsread(filename, sheet, xlRange);

AND THIS IS FOR TESTING

% load jaringan yang sudah dibuat pada proses pelatihan

load skripsi.mat

% Proses membaca data uji dari excel

filename = 'berhasil.xlsx';

sheet = 2;

xlRange = 'O1:R408';

Data = xlsread(filename, sheet, xlRange);

data_uji = Data(:,1:3)';

target_uji = Data(:,4)';

[m,n] = size(data_uji);

% Hasil prediksi

hasil_uji = sim(net_keluaran,data_uji);

nilai_error = hasil_uji-target_uji;

max_data = 4;

min_data = 1;

hasil_uji = ((hasil_uji-0.1)*(max_data-min_data)/0.8)+min_data;

save hasil_prediksi.mat

% Performansi hasil prediksi

error_MSE = (1/n)*sum(nilai_error.^2);

filename = 'berhasil.xlsx';

sheet = 2;

xlRange = 'K1025:N2038';

target_uji_asli = xlsread(filename, sheet, xlRange);

i don't know how to make a predict code. can someone help me?