NARX Neural Network test on new test set?

After training NARX net.I want to evaluate the model on independent test set "testX'".But it returns me an error.I am testing the model by forecastLoad = sim(net, testX')'.Do we need to add delays in test set also?i don't know where i am making a mistake.

%Create training set

trainInd = data.NumDate < datenum('2008-01-01');
trainX = X(trainInd,:);
trainY = data.SYSLoad(trainInd);

% Create test set to test later
testInd = data.NumDate >= datenum('2008-01-01');
testX = X(testInd,:);
testY = data.SYSLoad(testInd);
testDates = dates(testInd);

%Neural network

X = tonndata(trainX,true,false);
T = tonndata(trainY,true,false);

% Choose a Training Function

trainFcn = 'trainlm';  % Levenberg-Marquardt backpropagation.

% Create a Nonlinear Autoregressive Network with External Input
inputDelays = 1:25;
feedbackDelays = 1:25;
hiddenLayerSize = 10;
net = narxnet(inputDelays,feedbackDelays,hiddenLayerSize,'open',trainFcn);

% Prepare the Data for Training and Simulation

[x,xi,ai,t] = preparets(net,X,{},T);

% Setup Division of Data for Training, Validation, Testing
net.divideParam.trainRatio = 70/100;
net.divideParam.valRatio = 15/100;
net.divideParam.testRatio = 15/100;

% Train the Network
[net,tr] = train(net,x,t,xi,ai);

% Test the Network
y = net(x,xi,ai);
e = gsubtract(t,y);
performance = perform(net,t,y)
% View the Network
view(net)

%%Forecast using Neural Network Model
% Once the model is built, perform a forecast on the independent test set. 
load Data\testSet
forecastLoad = sim(net, testX')';

[Greg Heath]

Searc the NEWSGROUP and ANSWERS using

 greg narxnet

Hope this helps.

Greg

Answer 1

[Greg Heath]

The best way to begin:

 Upper case for cell variables
 Lowercase for noncells
 Subscript o for openloop (OL)
 Subscript c for closed loop (CL)

 Read X & T
 Define x & t using cell2mat 
 Determine sizes of x and t

 Use divideblock so that train, val & test 
 are sensibly ordered for predicting the 
 future using a constant timestep size.

 3-color plots of x= [xtrn xval xtst] and t = ...
 Use xtrn, ttrn, and nncorr to determine the 
   values of the significant input and output lags
 Plots of autocorrt and crosscorrxt with significant 
   values identified with 'o'

Searching NEWSGROUP and ANSWERS using

 greg narxnet

 should help clear up questions.

PS: To answer your last question:

You have to use new values for Xi and Ai to continue.

Hope this clears our confusion.

Thank you for formally accepting my answer

Greg

[Machine Learning Enthusiast]

My question was not answered clearly.The main focus was i am getting an error inline

forecastLoad = sim(net, testX')'

[Greg Heath]

See my revised answer above (You have to include new values for Xi, and Ai)