understanding the newff and train functions

I have been given a project to predict future exchange rates between two currencies based on exchange rates in the past. I need to create a neural network to accept 10 values and to give a one single value as the output. (10 past exchange rates as inputs and output is the predicted exchange rate.) P = [0 1 2 3 4 5 6 7 8 9 10]; T = [0 1 2 3 4 3 2 1 2 3 4]; I learnt that in a this kind of situation, there are only one input node and one output node. first value of the T vector is the output when the first value of the P vector is given as the input. I need to give 10 input values to the first layer of the network. How to use newff function here. I am only looking for newff function since I have been advised to use only newff. I hope someone will help me to overcome my issue. Thanks!

[Jo Men]

feedforwardnet

[idris]

@Viraj, having read your question, check out the link below

https://www.mathworks.com/matlabcentral/answers/77741-newff-create-a-feed-forward-backpropagation-network-obsoleted-in-r2010b-nnet-7-0

Answer 1

[Greg Heath]

NEWFF has been obsolete for 4 years. The current function to use for regression/curve-fitting is FITNET.

You only have 11 points resulting in 11 equations. By closing your eyes and imagining the plot of T vs P, you will "see" a 3rd order polynomial-type curve with an internal local maximum and an endpoint maximum. This should be able to be modeled with H = 2 hidden nodes and Nw = (1+1)*H+(H+1)*1 = 7 weights/biases.

This is straight forward. See the examples in

 help/doc newff

or, if you want to use the current function model

 help/doc fitnet.

To mitigate the possibility of an unfortunate assignment of initial random weights, design 10 or more nets.

Hope this helps.

Thank you for formally accepting my answer

Greg

[Viraj]

I have put that code in my question just as an example. That is not what I need to create the neural network for. As I mentioned I need a network to accept 10 inputs.

[Greg Heath]

MATLAB is a vector/matrix based language. The code tends to be relatively independent of the actual dimensions of inputs and outputs. For examples search the NEWSGROUP and ANSWERS with

 greg newff

 greg fitnet

[waqar ali]

hello MyNetwork = newff(pn,tn, [i] , {tf}, 'trainlm');

i am trying to use newff function ,but i received this error , i am using matlab 2013 , any can tell me the reason of this error "Error using newff>new_5p1 (line 172) Layer sizes is not a row vector of positive integers.

Error in newff>create_network (line 130) net = new_5p1(varargin{:});

Error in newff (line 102) out1 = create_network(varargin{:});

Answer 2

[ilhem ouerghui]

Iam using Matlab 2016, I tried to use the function:

net_RN=newff(minmax(app2),[nbre_caract,Nero_cache,1]);

with:

nbre_caract=size(app2) && Nero_cache = 3

but i get this error:

Warning: NEWFF used in an obsolete way.

and from the help: The recommended function is feedforwardnet

how can I use this function please?

[Walter Roberson]

It is a warning, you can ignore it.

[ilhem ouerghui]

ok thanks for your answer

[Steven Lord]

You can ignore it, but I recommend reading the documentation for feedforwardnet and using that function as its documentation describes instead.

Answer 3

[abdelhafid benchikh]

Hi everyone I want to understand how the newff function work I means how can I use it and thanks

[Walter Roberson]

You can go back to the last time it was documented, http://www.mathworks.com/help/releases/R2010a/toolbox/nnet/newff.html in R2010a.

If you are using a release newer than R2010a, then don't use newff(), use feedforwardnet() instead.

Answer 4

[FuWei Shen]

great, it is useful.