Neural Network Toolbox™ 6 User’s Guide Howard Demuth Mark Beale Martin Hagan How to Contact The MathWorks www.mathworks.com Web comp.soft-sys.matlab Newsgroup www.mathworks.com/contact_TS.html Technical support suggest@mathworks.com Product enhancement suggestions bugs@mathworks.com Bug reports doc@mathworks.com Documentation error reports service@mathworks.com Order status, license renewals, passcodes info@mathworks.com Sales, pricing, and general information 508-647-7000 (Phone) 508-647-7001 (Fax) The MathWorks, Inc. 3 Apple Hill Drive Natick, MA 01760-2098 For contact information about worldwide offices, see the MathWorks Web site. Neural Network Toolbox™ User’s Guide © COPYRIGHT 1992–2009 by The MathWorks, Inc. The software described in this document is furnished under a license agreement. The software may be used or copied only under the terms of the license agreement. 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Revision History June 1992 First printing April 1993 Second printing January 1997 Third printing July 1997 Fourth printing January 1998 Fifth printing Revised for Version 3 (Release 11) September 2000 Sixth printing Revised for Version 4 (Release 12) June 2001 Seventh printing Minor revisions (Release 12.1) July 2002 Online only Minor revisions (Release 13) January 2003 Online only Minor revisions (Release 13SP1) June 2004 Online only Revised for Version 4.0.3 (Release 14) October 2004 Online only Revised for Version 4.0.4 (Release 14SP1) October 2004 Eighth printing Revised for Version 4.0.4 March 2005 Online only Revised for Version 4.0.5 (Release 14SP2) March 2006 Online only Revised for Version 5.0 (Release 2006a) September 2006 Ninth printing Minor revisions (Release 2006b) March 2007 Online only Minor revisions (Release 2007a) September 2007 Online only Revised for Version 5.1 (Release 2007b) March 2008 Online only Revised for Version 6.0 (Release 2008a) October 2008 Online only Revised for Version 6.0.1 (Release 2008b) March 2009 Online only Revised for Version 6.0.2 (Release 2009a) [...]... train the network, enter: net=train(net,houseInputs,houseTargets); During training, the following training window opens This window displays training progress and allows you to interrupt training at any point by clicking Stop Training 1-8 Fitting a Function This example used the train function All the input vectors to the network appear at once in a batch Alternatively, you can present the input vectors... problem in three ways: • Use a command-line function, as described in “Using Command-Line Functions” on page 1-7 • Use a graphical user interface, nftool, as described in “Using the Neural Network Fitting Tool GUI” on page 1-13 • Use nntool, as described in “Graphical User Interface” on page 3-23 Defining a Problem To define a fitting problem for the toolbox, arrange a set of Q input vectors as columns in. .. clustering 1-2 Using the Documentation Using the Documentation The neuron model and the architecture of a neural network describe how a network transforms its input into an output This transformation can be viewed as a computation This first chapter gives you an overview of the Neural Network Toolbox product and introduces you to the following tasks: • Training a neural network to fit a function • Training... systems Neural networks can also be trained to solve problems that are difficult for conventional computers or human beings The toolbox emphasizes the use of neural network paradigms that build up to—or are themselves used in engineering, financial, and other practical applications The next sections explain how to use three graphical tools for training neural networks to solve problems in function fitting,... Train the network The network uses the default Levenberg-Marquardt algorithm for training The application randomly divides input vectors and target vectors into three sets as follows: - 60% are used for training - 20% are used to validate that the network is generalizing and to stop training before overfitting - The last 20% are used as a completely independent test of network generalization To train... describes three practical neural network control system applications, including neural network model predictive control, model reference adaptive control, and a feedback linearization controller Chapter 11, “Applications” describes other neural network applications Business Applications The 1988 DARPA Neural Network Study [DARP88] lists various neural network applications, beginning in about 1984 with the... vectors one at a time using the adapt function “Training Styles” on page 2-20 describes the two training approaches This training stopped when the validation error increased for six iterations, which occurred at iteration 23 If you click Performance in the training window, a plot of the training errors, validation errors, and test errors appears, as shown in the following figure In this example, the result... There, the network is adjusted, based on a comparison of the output and the target, until the network output matches the target Typically, many such input/target pairs are needed to train a network Target Input Neural Network including connections (called weights) between neurons Compare Output Adjust weights Neural networks have been trained to perform complex functions in various fields, including pattern... and train again • Increase the number of hidden neurons • Increase the number of training vectors 1-11 1 Getting Started • Increase the number of input values, if more relevant information is available • Try a different training algorithm (see “Speed and Memory Comparison” on page 5-34) In this case, the network response is satisfactory, and you can now use sim to put the network to use on new inputs... analysis, machine vision, voice synthesis, and nonlinear modeling Entertainment Animation, special effects, and market forecasting Financial Real estate appraisal, loan advising, mortgage screening, corporate bond rating, credit-line use analysis, credit card activity tracking, portfolio trading program, corporate financial analysis, and currency price prediction Industrial Prediction of industrial processes,