Hey I need to know how to know how many neurons?

I would like how to use nntool, please could anyone help me, or tell me where I could find information about all the training functions, and performance functions.

[John D'Errico]

How many? Use enough, but not too many. Questions like this are impossible to answer, because the answer depends on your problem.

Start by reading things like

doc nntool

But really, it sounds like you need to learn fundamental information about neural networks. For that you may need to read a book.

Answer 1

[Greg Heath]

Search the NEWSGROUP and ANSWERS using

 Ntrneq Nw

where I have used the criterion that the number of UNKNOWN weights, Nw, should not exceed the number of training EQUATIONS Ntrneq.

               No. of SEARCH HITS

            NEWSGROUP      ANSWERS
 Ntrneq Nw    43            152

This yields an upperbound, Hub, on the number of hidden nodes in a single hidden layer net.

If more hidden nodes are required, one can replace the default training function TRAINLM with TRAINBR

 help trainbr
 doc trainbr

Hope this helps.

Thank you for formally acceptingmy answer

Greg

[Andres Romero]

thank you so much... and do you suggest me a book of neuronal network?

[Greg Heath]

Sorry, I am an old geezer who is not familiar with the recent literature.

Why don't you post a request in the NEWSGROUP?