what is x,t and y variables in this code?

5 次查看（过去 30 天）
sankari senthil
sankari senthil 2017-2-1
评论： Walter Roberson 2019-9-15
[x,t] = simplefit_dataset;
net = feedforwardnet(10);
net = train(net,x,t);
view(net)
y = net(x);
perf = perform(net,y,t)

请先登录，再回答此问题。

回答（3 个）

Greg Heath
Greg Heath 2017-2-1
x is the input matrix with N I-dimensional input columns
t is the output target matrix with N O-dimensional output target columns
vart1 = mean(var(t',1)) is the mean target variance
y is the output matrix with N O-dimensional output columns
e = t - y is the error matrix
NMSE = mse(e)/vart1 is the normalized output mean-squared-error
I prefer NMSE < 0.01 as a goal for regression and pattern-recognition,
NMSEo < 0.001 as a goal for open-loop time-series and
NMSEc < 0.01 as a goal for closed-loop time-series
Hope this helps.
Thank you for formally accepting my answer
Greg
Walter Roberson
Walter Roberson 2017-2-1
x is the data. t is the class information.
y is the result of running prediction using the input data. When the prediction for an input does not match the known target for the input then the Neural Net is not as good is it could be.
Sadiq Akbar
Sadiq Akbar 2019-9-11
[x,t] = simplefit_dataset;
Using this how can I enter my own inputs and traget data. e.g. if my input=[1; 2; 3; 4; 5]; and my target=[1 2 3 4;2 4 6 8;3 6 9 12;4 8 12 16;5 10 15 20]; Now WhenI eneter my this data via command window and enter these commands also i.e.
input=[1; 2; 3; 4; 5];
target=[1 2 3 4;2 4 6 8;3 6 9 12;4 8 12 16;5 10 15 20];
net = fitnet(10);
view(net)
net = train(net,x,yes);
view(net)
yes = net(x);
perf = perform(net,yes,t)
net = fitnet(10,'trainbr');
net = train(net,x,t);
yes = net(x);
perf = perform(net,yes,t)
I get this error:
RefFitNetExample
Undefined function or variable 'x'.
Error in RefFitNetExample (line 19)
net = train(net,x,yes);
So how to tacke this problem.
  3 个评论
显示 1更早的评论
Sadiq Akbar
Sadiq Akbar 2019-9-15
Input data is always in the form of vector and output may be greater than input as in my case. You mean to say we cannot treat this with above code. If yes , then how can we tackle this problem please?

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Modeling and Prediction with NARX and Time-Delay Networks 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by