Invalid training data. Sequence responses must have the same sequence length as the corresponding predictors.

my data is n*1, I apply LSTM to analysis，，，，choose：

k =3; %滑动窗口设置为1 具体设多少需要衡量

for i = 1:size(dataTrainStandardized)-k+1

XTrain(:,i) = dataTrainStandardized(i:i+k-1,:); %将其分为101个序列，每个序列长度500，特征5个

YTrain(:,i)= dataTrainStandardized(i+k-1,:);

end

inputsize= 3;

outputsize = 1;

numHiddenUnits = 20;

layers = [sequenceInputLayer(inputsize)

lstmLayer(numHiddenUnits)

dropoutLayer(0.5)%防止过拟合

fullyConnectedLayer(outputsize)

regressionLayer];

options = trainingOptions('adam', ...

'MaxEpochs',500,...

'MiniBatchSize',16, ...

'GradientThreshold',1, ...%梯度下降阈值

'InitialLearnRate',0.005, ...

'LearnRateSchedule','piecewise', ...

'LearnRateDropPeriod',250, ...%

'LearnRateDropFactor',0.5, ...

'ValidationData',{XTrain,YTrain}, ...

'ValidationFrequency',1, ...

'Verbose',1, ...

'Plots','training-progress');

%% Train LSTM Network

[net tr] = trainNetwork(XTrain,YTrain,layers,options);

but error is Invalid training data. Sequence responses must have the same sequence length as the corresponding predictors.

look for help！！！！thank you