Artificial Neural Network for PHP project https://ann.thwien.de/w/Main_Page MediaWiki 1.39.17 first-letter Media Special Talk User User talk Artificial Neural Network for PHP Artificial Neural Network for PHP talk File File talk MediaWiki MediaWiki talk Template Template talk Help Help talk Category Category talk 0 1 438 434 2025-10-14T14:11:19Z Thwien 2 438 wikitext text/x-wiki __NOTOC__ <big>'''ANN - Artificial Neural Network for PHP'''</big> This project realizes a '''neural network topology called ''[[multilayer perceptron]]'' for PHP''' environments. The source code is based on a work by ''Eddy Young'' in 2002. Several improvements and changes on this implementation are done by ''Thomas Wien'' ([https://thwien.de thwien.de] - Germany) since 2007. You get the PHP source in the section [[Download]]. Please, consider the [[Copyright]]. To get a short idea what is the benefit of neural networks have a look at page [[Neural Networks]]. == Project backgroud == Since 1992 I have been fascinated by the workings of neural networks, especially multilayer perceptrons. In the early days I planned to implement and use such networks in PHP projects. After taking over Eddy’s project in 2007 and releasing version 2.3.0 in 2012, a lot has changed in how we work with neural networks. Today large‑language models are ubiquitous. Consequently, a PHP class that implements a simple multilayer perceptron may no longer be essential for practical applications, though these models still underpin many modern systems. Nonetheless, the PHP class remains a valuable educational tool for grasping the core concepts of contemporary neural networks. It can serve as part of training or learning exercises. Enjoy! == Overview == * [[Neural Networks]] * [[Multilayer perceptron|Multilayer Perceptron]] * [[Download]] * [[Installation]] * [[Examples]] * [[FAQ]] * [[Copyright]] == Versions and Change-Log == '''Version 3.0.0 by Thomas Wien''' (2025-10-04) [[Download]] * Full rework of all PHP scripts * Remaining functioniality reduced to fundamentaly function of neural network only * Phar support removed * PHP 8.2 is required '''Version 2.3.0 by Thomas Wien''' (2012-12-13) * Using traits for performance reasons * Checking php version for compatibility with ANN library * PHP 5.4.x or above '''Version 2.2.3 by Thomas Wien''' (2012-12-12) * Bugfix: Division by zero if training time below one second * Adding php version and sapi interface to network information * Test running on PHP 5.4 '''Version 2.2.2 by Thomas Wien''' (2011-07-04) * Redesign of network details * Considering cpu limits for calculation of network execution time '''Version 2.2.1 by Thomas Wien''' (2011-06-15) * Bug fix: Wrong output type detection in binary networks * Using Interface called \ANN\InterfaceLoadable to make easier decision of loadable objects. '''Version 2.2.0 by Thomas Wien''' (2011-06-01) * Introduction of namespaces as of PHP 5.3 * Dynamic learning rate * \ANN\Network::setLearningRate() is protected now * Bug fix: Wrong output type detection in some circumstances '''Version 2.1.7 by Thomas Wien''' (2011-06-15) * Bug fix: Wrong output type detection in binary networks '''Version 2.1.6 by Thomas Wien''' (2011-06-01) * Bug fix: Wrong output type detection in some circumstances '''Version 2.1.5 by Thomas Wien''' (2011-05-24) * Dividing method ANN_Math::random() in ANN_Math::randomDelta() and ANN_Math::randomWeight() * Better implementation of printing network details including __invoke() und __toString() converting '''Version 2.1.4 by Thomas Wien''' (2011-05-23) * Better calculation of remaining time of running the network * Fixing bug: generating random delta not correct * Adding momentum value * Simplified ANN_Neuron::adjustWeights() * Remove possible wrong calculation in ANN_Neuron::adjustWeights() on linear networks * Simplify ANN_Layer::calculateHiddenDeltas() '''Version 2.1.3 by Thomas Wien''' (2010-01-06) * Date input support class '''Version 2.1.2 by Thomas Wien''' (2009-12-26) * Classification support * Phar support (as of PHP 5.3.0) '''Version 2.1.1 by Thomas Wien''' (2009-12-23) * String association support '''Version 2.1.0 by Thomas Wien''' (2009-12-22) * Checking parameter counts on ANN_Values::input() and ANN_Values::output() * Removing protected method ANN_Neuron::getInputs() * Fixing bug: Error tolerance calculation in ANN_Network::isTrainingComplete() * Switching to Git version control * Moving all experimental code into branch * Removing all experimental code from master branch (due to performance and future development) '''Version 2.0.7 by Thomas Wien''' (2009-01-01) [[Download]] * Removing protected method ANN_Neuron::setOutput() * Removing protected unused method ANN_Layer::getInputs() * Removing protected unused property ANN_Layer::$arrInputs * More detailed exceptions to ANN_Filesystem::saveToFile() * Different distribution of activation calls across the layers * Different adjustments in ANN_Neuron::adjustWeights() depending on output type * Removing static local variables from ANN_Network::getNextIndexInputsToTrain() * Increasing math precision * Using class constants for output types (increasing performance) * Fixing bug: ANN_Neuron::getOutput() is float and not array '''Version 2.0.6 by Thomas Wien''' (2008-12-18) * Printing network details of output differences to their desired values * Complete rewritten code standard of variables * New class ANN_Values for defining input and output values * Code examples to phpdoc * Internal math precision defaults to 5 '''Version 2.0.5 by Thomas Wien''' (2008-12-16) * Adjustable output error tolerance between 0 and 10 per cent * Internal rounding of floats for performance issues * Loading class for all ANN classes (SPL autoload) * Renaming filename of ANN_Maths class * Improving code standard * Fixing bug: Comparison in ANN_InputValue and ANN_OutputValue '''Version 2.0.4 by Thomas Wien''' (2008-01-27) * Weight decay * QuickProp algorithm (experimental) * RProp algorithm (experimental) * Linear saturated activation function (experimental) * Individual learning rate algorithm (experimental) * Reducing of overfitting (no training if input pattern produces desired output) * Increasing performance on activation * Increasing performance on testing all patterns to their desired outputs * Increasing performance on calculating hidden deltas * Increasing performance by defining layer relation by construction * More details to printNetwork() * Fixing bug: learning rate is not part of saved delta value '''Version 2.0.3 by Thomas Wien''' (2008-01-17) * Support for dynamic learning rate * Automatic epoch determination * Automatic output type detection * Shuffling input patterns each epoch instead of randomized pattern access * Logging of network errors * Logging on each epoch instead of each training step * Avoiding distributed internal calls of setMomentum() and setLearningRate() * Extending display of network details * Fixing bug: runtime error on call of setMomentum() '''Version 2.0.2 by Thomas Wien''' (2008-01-14) * Client-Server model for distributed applications * Calculating total network error for csv logging '''Version 2.0.1 by Thomas Wien''' (2008-01-06) * Separation of classes to several files * Version control by Subversion * Performance issues * Graphical output of neural network topology * Logging of weights to csv file '''Version 2.0.0 by Thomas Wien''' (2007-12-17) * PHP 5.x support * PHPDoc documentation * Momentum support * Avoiding network overfitting * Linear / binary output * ANN_InputValue + ANN_OutputValue classes * Exceptions * Threshold function * Hyperbolic tangent transfer function * Several performance issues * Avoiding array_keys() & srand() due to performance * Changes in saving and loading network * Printing network details to browser * Fixing bug: initializing inputs to all hidden layers * Fixing bug: training for first hidden layer was skipped '''Version 1.0 by Eddy Young''' (2002) * Initial version b38jf1rg9i7ghjxefvz3lobp2kt14yo